Aldosterone Health Dictionary

Aldosterone: From 3 Different Sources


A hormone secreted by the adrenal cortex (the outer part of the adrenal glands). Aldosterone acts on the kidneys to regulate the concentrations of sodium and potassium in the blood and tissues and control blood pressure. Production of aldosterone is stimulated mainly by the action of angiotensin , a chemical produced by a series of reactions involving the enzymes renin and angiotensin-converting enzyme. Aldosterone production is also stimulated by the action of ACTH, which is produced by the pituitary gland.
Health Source: BMA Medical Dictionary
Author: The British Medical Association
Aldosterone is a hormone secreted by the adrenal cortex (see ADRENAL GLANDS). It plays an important part in maintaining the electrolyte balance of the body by promoting the reabsorption of sodium and the secretion of potassium by the renal tubules. It is thus of primary importance in controlling the volume of the body ?uids.
Health Source: Medical Dictionary
Author: Health Dictionary
n. a steroid hormone (see corticosteroid) that is synthesized and released by the adrenal cortex and acts on the kidney to regulate salt (potassium and sodium) and water balance.
Health Source: Oxford | Concise Colour Medical Dictionary
Author: Jonathan Law, Elizabeth Martin

Adrenal Glands

Also known as suprarenal glands, these are two small triangular ENDOCRINE GLANDS situated one upon the upper end of each kidney. (See diagram of ABDOMEN.)

Structure Each suprarenal gland has an enveloping layer of ?brous tissue. Within this, the gland shows two distinct parts: an outer, ?rm, deep-yellow cortical (see CORTEX) layer, and a central, soft, dark-brown medullary (see MEDULLA) portion. The cortical part consists of columns of cells running from the surface inwards, whilst in the medullary portion the cells are arranged irregularly and separated from one another by large capillary blood vessels.

Functions Removal of the suprarenal glands in animals is speedily followed by great muscular prostration and death within a few days. In human beings, disease of the suprarenal glands usually causes ADDISON’S DISEASE, in which the chief symptoms are increasing weakness and bronzing of the skin. The medulla of the glands produces a substance – ADRENALINE – the effects of which closely resemble those brought about by activity of the SYMPATHETIC NERVOUS SYSTEM: dilated pupils, hair standing on end, quickening and strengthening of the heartbeat, immobilisation of the gut, increased output of sugar from the liver into the bloodstream. Several hormones (called CORTICOSTEROIDS) are produced in the cortex of the gland and play a vital role in the metabolism of the body. Some (such as aldosterone) control the electrolyte balance of the body and help to maintain the blood pressure and blood volume. Others are concerned in carbohydrate metabolism, whilst others again are concerned with sex physiology. HYDROCORTISONE is the most important hormone of the adrenal cortex, controlling as it does the body’s use of carbohydrates, fats and proteins. It also helps to suppress in?ammatory reactions and has an in?uence on the immune system.... adrenal glands

Angiotensin

Angiotensin is a peptide that occurs in two forms: I and II. The former results from the action of the ENZYME, RENIN on alpha globulin (a protein) produced by the liver and passed into the blood. During passage of the blood through the lungs, angiotensin I is converted into an active form, angiotensin II, by an enzyme. This active form constricts the blood vessels and stimulates the release of two hormones – VASOPRESSIN and ALDOSTERONE – which raise the blood pressure. (See also

ANGIOTENSIN-CONVERTING ENZYME (ACE) INHIBITORS.)... angiotensin

Spironolactone

One of the group of substances known as spirolactones. These are steroids similar to ALDOSTERONE in structure which competitively act as inhibitors of it; they can thus antagonise the action of aldosterone in the renal tubules. As there is evidence that there is an increased output of aldosterone in oedematous conditions (see OEDEMA) – such as congestive heart failure, which accentuates the oedema – spironolactone is used, along with other DIURETICS.... spironolactone

Addison’s Disease

A disease causing failure of adrenal gland function, in particular deficiency of adrenal cortical hormones, mainly cortisol and aldosterone. Commonest causes are tuberculosis and auto- immune disease.

Symptoms: (acute) abdominal pain, muscle weakness, vomiting, low blood pressure due to dehydration, tiredness, mental confusion, loss of weight and appetite. Vomiting, dizzy spells. Increased dark pigmentation around genitals, nipples, palms and inside mouth. Persistent low blood pressure with occasional low blood sugar. Crisis is treated by increased salt intake. Research project revealed a craving for liquorice sweets in twenty five per cent of patients.

Herbs with an affinity for the adrenal glands: Parsley, Sarsaparilla, Wild Yam, Borage, Liquorice, Ginseng, Chaparral. Where steroid therapy is unavoidable, supplementation with Liquorice and Ginseng is believed to sustain function of the glands. Ginseng is supportive when glands are exhausted by prolonged stress. BHP (1983) recommends: Liquorice, Dandelion leaf.

Alternatives. Teas. Gotu Kola, Parsley, Liquorice root, Borage, Ginseng, Balm.

Tea formula. Combine equal parts: Balm and Gotu Kola. Preparation of teas and tea mixture: 1 heaped teaspoon to each cup boiling water: infuse 5-10 minutes; 1 cup 2 to 3 times daily.

Tablets/capsules. Ginseng, Seaweed and Sarsaparilla, Wild Yam, Liquorice. Dosage as on bottle. Formula. Combine: Gotu Kola 3; Sarsaparilla 2; Ginseng 1; Liquorice quarter. Doses. Powders: 500mg (two 00 capsules or one-third teaspoon). Liquid extracts: 30-60 drops. Tinctures: 1-2 teaspoons 2 to 3 times daily.

Formula. Alternative. Tinctures 1:5. Echinacea 20ml; Yellow Dock 10ml; Barberry 10ml; Sarsaparilla 10ml; Liquorice (liquid extract) 5ml. Dose: 1-2 teaspoons thrice daily.

Supplementation. Cod liver oil. Extra salt. B-Vitamins. Folic acid. ... addison’s disease

Conn’s Syndrome

A disorder caused by the secretion of excessive amounts of the hormone aldosterone by a noncancerous tumour of one of the adrenal glands. (See also aldosteronism.)... conn’s syndrome

Aldosteronism

A disorder that results from the excessive production of the hormone aldosterone from one or both adrenal glands. Aldosteronism caused by an adrenal tumour is known as Conn’s syndrome. Aldosteronism may also be caused by disorders, such as heart failure or liver damage, that reduce the flow of blood through the kidneys. Reduced blood flow through the kidneys leads to overproduction of renin and angiotensin, which, in turn, leads to excessive aldosterone production.

Symptoms are directly related to the actions of aldosterone. Too much sodium is retained in the body, leading to a rise in blood pressure, and excess potassium is lost in the urine. Low potassium causes tiredness and muscle weakness and impairs kidney function, leading to thirst and overproduction of urine.

Treatment in all cases includes restriction of dietary salt and use of the diuretic drug spironolactone.

If the cause of aldosteronism is an adrenal tumour, this may be surgically removed.... aldosteronism

Addison’s Disease

The cause of Addison’s disease (also called chronic adrenal insu?ciency and hypocortisolism) is a de?ciency of the adrenocortical hormones CORTISOL, ALDOSTERONE and androgens (see ANDROGEN) due to destruction of the adrenal cortex (see ADRENAL GLANDS). It occurs in about 1 in 25,000 of the population. In the past, destruction of the adrenal cortex was due to TUBERCULOSIS (TB), but nowadays fewer than 20 per cent of patients have TB while 70 per cent suffer from autoimmune damage. Rare causes of Addison’s disease include metastases (see METASTASIS) from CARCINOMA, usually of the bronchus; granulomata (see GRANULOMA); and HAEMOCHROMATOSIS. It can also occur as a result of surgery for cancer of the PITUITARY GLAND destroying the cells which produce ACTH (ADRENOCORTICOTROPHIC HORMONE)

– the hormone which provokes the adrenal cortex into action.

Symptoms The clinical symptoms appear slowly and depend upon the severity of the underlying disease process. The patient usually complains of appetite and weight loss, nausea, weakness and fatigue. The skin becomes pigmented due to the increased production of ACTH. Faintness, especially on standing, is due to postural HYPOTENSION secondary to aldosterone de?ciency. Women lose their axillary hair and both sexes are liable to develop mental symptoms such as DEPRESSION. Acute episodes – Addisonian crises – may occur, brought on by infection, injury or other stressful events; they are caused by a fall in aldosterone levels, leading to abnormal loss of sodium and water via the kidneys, dehydration, low blood pressure and confusion. Patients may develop increased tanning of the skin from extra pigmentation, with black or blue discoloration of the skin, lips, mouth, rectum and vagina occurring. ANOREXIA, nausea and vomiting are common and the sufferer may feel cold.

Diagnosis This depends on demonstrating impaired serum levels of cortisol and inability of these levels to rise after an injection of ACTH.

Treatment consists in replacement of the de?cient hormones. HYDROCORTISONE tablets are commonly used; some patients also require the salt-retaining hormone, ?udrocortisone. Treatment enables them to lead a completely normal life and to enjoy a normal life expectancy. Before surgery, or if the patient is pregnant and unable to take tablets, injectable hydrocortisone may be needed. Rarely, treated patients may have a crisis, perhaps because they have not been taking their medication or have been vomiting it. Emergency resuscitation is needed with ?uids, salt and sugar. Because of this, all patients should carry a card detailing their condition and necessary management. Treatment of any complicating infections such as tuberculosis is essential. Sometimes DIABETES MELLITUS coexists with Addison’s disease and must be treated.

Secondary adrenal insu?ciency may occur in panhypopituitarism (see PITUITARY GLAND), in patients treated with CORTICOSTEROIDS or after such patients have stopped treatment.... addison’s disease

Endocrine Glands

Organs whose function it is to secrete into the blood or lymph, substances known as HORMONES. These play an important part in general changes to or the activities of other organs at a distance. Various diseases arise as the result of defects or excess in the internal secretions of the di?erent glands. The chief endocrine glands are:

Adrenal glands These two glands, also known as suprarenal glands, lie immediately above the kidneys. The central or medullary portion of the glands forms the secretions known as ADRENALINE (or epinephrine) and NORADRENALINE. Adrenaline acts upon structures innervated by sympathetic nerves. Brie?y, the blood vessels of the skin and of the abdominal viscera (except the intestines) are constricted, and at the same time the arteries of the muscles and the coronary arteries are dilated; systolic blood pressure rises; blood sugar increases; the metabolic rate rises; muscle fatigue is diminished. The super?cial or cortical part of the glands produces steroid-based substances such as aldosterone, cortisone, hydrocortisone, and deoxycortone acetate, for the maintenance of life. It is the absence of these substances, due to atrophy or destruction of the suprarenal cortex, that is responsible for the condition known as ADDISON’S DISEASE. (See CORTICOSTEROIDS.)

Ovaries and testicles The ovary (see OVARIES) secretes at least two hormones – known, respectively, as oestradiol (follicular hormone) and progesterone (corpus luteum hormone). Oestradiol develops (under the stimulus of the anterior pituitary lobe – see PITUITARY GLAND below, and under separate entry) each time an ovum in the ovary becomes mature, and causes extensive proliferation of the ENDOMETRIUM lining the UTERUS, a stage ending with shedding of the ovum about 14 days before the onset of MENSTRUATION. The corpus luteum, which then forms, secretes both progesterone and oestradiol. Progesterone brings about great activity of the glands in the endometrium. The uterus is now ready to receive the ovum if it is fertilised. If fertilisation does not occur, the corpus luteum degenerates, the hormones cease acting, and menstruation takes place.

The hormone secreted by the testicles (see TESTICLE) is known as TESTOSTERONE. It is responsible for the growth of the male secondary sex characteristics.

Pancreas This gland is situated in the upper part of the abdomen and, in addition to the digestive enzymes, it produces INSULIN within specialised cells (islets of Langerhans). This controls carbohydrate metabolism; faulty or absent insulin production causes DIABETES MELLITUS.

Parathyroid glands These are four minute glands lying at the side of, or behind, the thyroid (see below). They have a certain e?ect in controlling the absorption of calcium salts by the bones and other tissues. When their secretion is defective, TETANY occurs.

Pituitary gland This gland is attached to the base of the brain and rests in a hollow on the base of the skull. It is the most important of all endocrine glands and consists of two embryologically and functionally distinct lobes.

The function of the anterior lobe depends on the secretion by the HYPOTHALAMUS of certain ‘neuro-hormones’ which control the secretion of the pituitary trophic hormones. The hypothalamic centres involved in the control of speci?c pituitary hormones appear to be anatomically separate. Through the pituitary trophic hormones the activity of the thyroid, adrenal cortex and the sex glands is controlled. The anterior pituitary and the target glands are linked through a feedback control cycle. The liberation of trophic hormones is inhibited by a rising concentration of the circulating hormone of the target gland, and stimulated by a fall in its concentration. Six trophic (polypeptide) hormones are formed by the anterior pituitary. Growth hormone (GH) and prolactin are simple proteins formed in the acidophil cells. Follicle-stimulating hormone (FSH), luteinising hormone (LH) and thyroid-stimulating hormone (TSH) are glycoproteins formed in the basophil cells. Adrenocorticotrophic hormone (ACTH), although a polypeptide, is derived from basophil cells.

The posterior pituitary lobe, or neurohypophysis, is closely connected with the hypothalamus by the hypothalamic-hypophyseal tracts. It is concerned with the production or storage of OXYTOCIN and vasopressin (the antidiuretic hormone).

PITUITARY HORMONES Growth hormone, gonadotrophic hormone, adrenocorticotrophic hormone and thyrotrophic hormones can be assayed in blood or urine by radio-immunoassay techniques. Growth hormone extracted from human pituitary glands obtained at autopsy was available for clinical use until 1985, when it was withdrawn as it is believed to carry the virus responsible for CREUTZFELDT-JAKOB DISEASE (COD). However, growth hormone produced by DNA recombinant techniques is now available as somatropin. Synthetic growth hormone is used to treat de?ciency of the natural hormone in children and adults, TURNER’S SYNDROME and chronic renal insu?ciency in children.

Human pituitary gonadotrophins are readily obtained from post-menopausal urine. Commercial extracts from this source are available and are e?ective for treatment of infertility due to gonadotrophin insu?ciency.

The adrenocorticotrophic hormone is extracted from animal pituitary glands and has been available therapeutically for many years. It is used as a test of adrenal function, and, under certain circumstances, in conditions for which corticosteroid therapy is indicated (see CORTICOSTEROIDS). The pharmacologically active polypeptide of ACTH has been synthesised and is called tetracosactrin. Thyrotrophic hormone is also available but it has no therapeutic application.

HYPOTHALAMIC RELEASING HORMONES which affect the release of each of the six anterior pituitary hormones have been identi?ed. Their blood levels are only one-thousandth of those of the pituitary trophic hormones. The release of thyrotrophin, adrenocorticotrophin, growth hormone, follicle-stimulating hormone and luteinising hormone is stimulated, while release of prolactin is inhibited. The structure of the releasing hormones for TSH, FSH-LH, GH and, most recently, ACTH is known and they have all been synthesised. Thyrotrophin-releasing hormone (TRH) is used as a diagnostic test of thyroid function but it has no therapeutic application. FSH-LH-releasing hormone provides a useful diagnostic test of gonadotrophin reserve in patients with pituitary disease, and is now used in the treatment of infertility and AMENORRHOEA in patients with functional hypothalamic disturbance. As this is the most common variety of secondary amenorrhoea, the potential use is great. Most cases of congenital de?ciency of GH, FSH, LH and ACTH are due to defects in the hypothalamic production of releasing hormone and are not a primary pituitary defect, so that the therapeutic implication of this synthesised group of releasing hormones is considerable.

GALACTORRHOEA is frequently due to a microadenoma (see ADENOMA) of the pituitary. DOPAMINE is the prolactin-release inhibiting hormone. Its duration of action is short so its therapeutic value is limited. However, BROMOCRIPTINE is a dopamine agonist with a more prolonged action and is e?ective treatment for galactorrhoea.

Thyroid gland The functions of the thyroid gland are controlled by the pituitary gland (see above) and the hypothalamus, situated in the brain. The thyroid, situated in the front of the neck below the LARYNX, helps to regulate the body’s METABOLISM. It comprises two lobes each side of the TRACHEA joined by an isthmus. Two types of secretory cells in the gland – follicular cells (the majority) and parafollicular cells – secrete, respectively, the iodine-containing hormones THYROXINE (T4) and TRI-IODOTHYRONINE (T3), and the hormone CALCITONIN. T3 and T4 help control metabolism and calcitonin, in conjunction with parathyroid hormone (see above), regulates the body’s calcium balance. De?ciencies in thyroid function produce HYPOTHYROIDISM and, in children, retarded development. Excess thyroid activity causes thyrotoxicosis. (See THYROID GLAND, DISEASES OF.)... endocrine glands

Hypernatraemia

A SERUM sodium concentration that is above normal. The condition is usually caused by dehydration (either from inadequate intake or excessive loss of water); occasionally it may be caused by excessive sodium intake, and rarely by a raised level of ALDOSTERONE hormone.... hypernatraemia

Medicinal Yams

Dioscorea spp.

Dioscoreaceae

The growing need for steroidal drugs and the high cost of obtaining them from animal sources led to a widespread search for plant sources of steroidal sapogenins, which ultimately led to the most promising one. It is the largest genus of the family constituted by 600 species of predominantly twining herbs. Among the twining species, some species twine clockwise while others anti-clockwise (Miege, 1958). All the species are dioceous and rhizomatous. According to Coursey (1967), this genus is named in honour of the Greek physician Pedenios Dioscorides, the author of the classical Materia Medica Libri Quinque. Some of the species like D. alata and D. esculenta have been under cultivation for a long time for their edible tubers. There are about 15 species of this genus containing diosgenin. Some of them are the following (Chopra et al, 1980).

D. floribunda Mart. & Gal.

D. composita Hemsl; syn. D. macrostachya Benth.

D. deltoidea Wall. ex Griseb; syn. D. nepalensis Sweet ex Bernardi.

D. aculeata Linn. syn. D. esculenta

D. alata Linn. syn. D. atropurpurea Roxb.

D. Globosa Roxb; D. purpurea Roxb; D. rubella Roxb.

D. bulbifera Linn. syn. D. crispata Roxb.

D. pulchella Roxb.; D. sativa Thunb. Non Linn.

D. versicolor Buch. Ham. Ex Wall.

D. daemona Roxb. syn. D. hispida Dennst.

D. oppositifolia Linn.

D. pentaphylla Linn. syn. D. jacquemontii Hook. f.

D. triphylla Linn.

D. prazeri Prain & Burkil syn. D. clarkei Prain & Burkill

D. deltoidea Wall. var. sikkimensis Prain

D. sikkimensis Prain & Burkill

Among the above said species, D. floribunda, D. composita and D. deltoidea are widely grown for diosgenin production.

1. D. floribunda Mart. & Gal D. floribunda Mart. & Gal. is an introduction from central America and had wide adaptation as it is successfully grown in Karnataka, Assam, Meghalaya, Andaman and Goa. The vines are glabrous and left twining. The alternate leaves are borne on slender stems and have broadly ovate or triangular ovate, shallowly cordate, coriaceous lamina with 9 nerves. The petioles are 5-7cm long, thick and firm. Variegation in leaves occurs in varying degrees. The male flowers are solitary and rarely in pairs. Female flowers have divericate stigma which is bifid at apex. The capsule is obovate and seed is winged all round. The tubers are thick with yellow coloured flesh, branched and growing upto a depth of 30cm (Chadha et al, 1995).

2. D. composita Hemsl.

D. composita Hemsl. according to Knuth (1965) has the valid botanical name as D. macrostachya Benth. However, D. composita is widely used in published literature. It is a Central American introduction into Goa, Jammu, Bangalore, Anaimalai Hills of Tami Nadu and Darjeeling in W. Bengal. The vines are right twinning and nearly glabrous. The alternate leaves have long petioles, membraneous or coriaceous lamina measuring upto 20x18cm, abruptly acute or cuspidate-acuminate, shallowly or deeply cordate, 7-9 nerved. The fasciculate-glomerate inflorescence is single or branched with 2 or 3 sessile male flowers having fertile stamens. Male fascicle is 15-30cm long. The female flowers have bifid stigma. Tubers are large, white and deep-rooted (upto 45cm) (Chadha et al, 1995).

3. D. deltoidea Wall. ex. Griseb.

D. deltoidea Wall. ex. Griseb. is distributed throughout the Himalayas at altitudes of 1000-3000m extending over the states of Jammu-Kashmir, H. P, U. P, Sikkim and further into parts of W. Bengal. The glabrous and left twining stem bears alternate petiolate leaves. The petioles are 5-12 cm long. The lamina is 5-15cm long and 4-12cm wide widely cordate. The flowers are borne on axillary spikes, male spikes 8-40cm long and stamens 6. Female spikes are 15cm long, 3. 5cm broad and 4-6 seeded. Seeds are winged all round. Rhizomes are lodged in soil, superficial, horizontal, tuberous, digitate and chestnut brown in colour (Chadha et al, 1995). D. deltoidea tuber grows parallel to ground covered by small scale leaves and is described as rhizome. The tubers are morphologically cauline in structure with a ring of vascular bundles in young tubers which appear scattered in mature tubers (Purnima and Srivastava, 1988). Visible buds are present unlike in D. floribunda and D. composita where the buds are confined to the crown position (Selvaraj et al, 1972).

Importance of Diosgenin: Diosgenin is the most important sapogenin used as a starting material for synthesis of a number of steroidal drugs. For commercial purposes, its -isomer, yamogenin is also taken as diosgenin while analysing the sample for processing. Various steroidal drugs derived from diosgenin by artificial synthesis include corticosteroids, sex hormones, anabolic steroids and oral contraceptives. Corticosteroids are the most important group of steroidal drugs synthesized from diosgenin. First group of corticosteroids regulates carbohydrate and protein metabolism. The second group consists of aldosterone, which controls balance of potassium, sodium and water in the human body. The glucocorticoids in the form of cortisone and hydrocortisone are used orally, intramuscularly or topically for treatment of rheumatoid arthritis, rheumatic fever, other collegen diseases, ulcerative colitis, certain cases of asthma and a number of allergic diseases affecting skin, eye and the ear. These are also used for treatment of gout and a variety of inflammations of skin, eye and ear and as replacement therapy in Addison’s diseases. The minerato corticoides, desoxycorticosterone or desoxycortone are used in restoring kidney functions in cases of cortical deficiency and Addison’s disease.

Both male and female sex hormones are also synthesized from disosgenin. The main male sex hormone (androgen) which is produced from disogenin is testosterone. The main female sex hormones produced are oestrogen and progesterone. Recently oestrogen has also been used in cosmetic lotions and creams to improve the tone and colour of skin. One of the main uses of progesterone during recent years has been as antifertility agent for oral contraceptives. These artificial steroids have increased oral activity and fewer side effects, as they can be used in reduced doses. Oral contraceptives are also used for animals like pigs, cows and sheep to control fertility and to give birth at a prescribed period in a group of animals at the same time. These compounds are also used to reduce the interval between the lactation periods to have more milk and meat production. Anti-fertility compounds are also used as a pest-control measure for decreasing the multiplication of pests like rodents, pigeons and sea gulls (Husain et al, 1979).

Although yam tubers contain a variety of chemical substances including carbohydrates, proteins, alkaloids and tannins, the most important constituents of these yams are a group of saponins which yield sapogenins on hydrolysis. The most imp ortant sapogenin found in Dioscorea are diosgenin, yamogenin and pannogenin. Diosgenin is a steroid drug precursor. The diogenin content varies from 2-7% depending on the age of the tubers. Saponins including 5 spirastanol glucoside and 2 furostanol glucoside, 4 new steroid saponins, floribunda saponins C, D, E and F. Strain of A and B are obtained from D. floribunda (Husain et al, 1979). Rhizomes of D. deltoidea are a rich source of diosgenin and its glycoside. Epismilagenin and smilagenone have been isolated from D. deltoidea and D. prazeri (Chakravarti et al, 1960; 1962). An alkaloid dioscorine has been known to occur in D. hispida (Bhide et al,1978). Saponin of D. prazeri produced a fall of blood pressure when given intravenously and saponin of D. deltoidea has no effect on blood pressure (Chakravarti et al,1963). Deltonin, a steroidal glycoside, isolated from rhizomes of D. deltoidea showed contraceptive activity (Biokova et al, 1990).

Agrotechnology: Dioscorea species prefer a tropical climate without extremity in temperature. It is adapted to moderate to heavy rainfall area. Dioscorea plants can be grown in a variety of soils, but light soil is good, as harvesting of tubers is easier in such soils. The ideal soil pH is 5.5-6.5 but tolerates fairly wide variation in soil pH. Dioscorea can be propagated by tuber pieces, single node stem cuttings or seed. Commercial planting is normally established by tuber pieces only. Propagation through seed progeny is variable and it may take longer time to obtain tuber yields. IIHR, Bangalore has released two improved varieties, FB(c) -1, a vigorously growing strain relatively free from diseases and Arka Upkar, a high yielding clone. Three types of tuber pieces can be distinguished for propagation purpose, viz. (1) crown (2) median and (3) tip, of which crowns produce new shoots within 30 days and are therefore preferred. Dipping of tuber pieces for 5 minutes in 0.3% solution of Benlate followed by dusting the cut ends with 0.3% Benlate in talcum powder in mo ist sand beds effectively checks the tuber rot. The treatment is very essential for obtaining uniform stand of the crop. The best time of planting is the end of April so that new sprouts will grow vigorously during the rainy season commencing in June in India. Land is to be prepared thoroughly until a fine tilth is obtained. Deep furrows are made at 60cm distance with the help of a plough. The stored tuber pieces which are ready for planting is to be planted in furrows with 30cm between the plants for one year crop and 45cm between the plants for 2 year crop at about 0.5 cm below soil level. The new sprouts are to be staked immediately. After sprouting is complete, the plants are to be earthed up. Soil from the ridges may be used for earthing up so that the original furrows will become ridges and vice versa. Dioscorea requires high organic matter for good tuber formation. Besides a basal doze of 18-20t of FYM/ha, a complete fertilizer dose of 300kg N, 150kg P2O5 and K2O each are to be applied per hectare. P and K are to be applied in two equal doses one after the establishment of the crop during May-June and the other during vigorous growth period of the crop (August- September). Irrigation may be given at weekly intervals in the initial stage and afterwards at about 10 days interval. Dioscorea vines need support for their optimum growth and hence the vines are to be trailed over pandal system or trellis. Periodic hand weeding is essential for the first few months. Intercropping with legumes has been found to smother weeds and provide extra income. The major pests of Dioscorea are the aphids and red spider mites. Aphids occur more commonly on young seedlings and vines. Young leaves and vine tips eventually die if aphids are not controlled. Red spider mites attack the underside of the leaves at the base near the petiole. Severe infestations result in necrotic areas, which are often attacked by fungi. Both aphids and spider mites can be very easily controlled by Kelthane. No serious disease is reported to infect this crop. The tubers grow to about 25-30 cm depth and hence harvesting is to be done by manual labour. The best season for harvesting is Feb-March, coinciding with the dry period. On an average 50-60t/ha of fresh tubers can be obtained in 2 years duration. Diosgenin content tends to increase with age, 2.5% in first year and 3-3.5% in the second year. Hence, 2 year crop is economical (Kumar et al, 1997).... medicinal yams

Adrenal Tumours

Cancerous or noncancerous tumours in the adrenal glands, usually causing excess secretion of hormones. Adrenal tumours are rare. Tumours of the adrenal cortex may secrete aldosterone, causing primary aldosteronism, or hydrocortisone, causing Cushing’s syndrome. Tumours of the medulla may cause excess secretion of adrenaline and noradrenaline. Two types of tumour affect the medulla: phaeochromocytoma and neuroblastoma, which affects children. These tumours cause intermittent hypertension and sweating attacks. Surgical removal of a tumour usually cures these conditions.... adrenal tumours

Adrenogenital Syndrome

An inherited condition, the adrenogenital syndrome – also known as congenital adrenal hyperplasia – is an uncommon disorder affecting about 1 baby in 7,500. The condition is present from birth and causes various ENZYME defects as well as blocking the production of HYDROCORTISONE and ALDOSTERONE by the ADRENAL GLANDS. In girls the syndrome often produces VIRILISATION of the genital tract, often with gross enlargement of the clitoris and fusion of the labia so that the genitalia may be mistaken for a malformed penis. The metabolism of salt and water may be disturbed, causing dehydration, low blood pressure and weight loss; this can produce collapse at a few days or weeks of age. Enlargement of the adrenal glands occurs and the affected individual may also develop excessive pigmentation in the skin.

When virilisation is noted at birth, great care must be taken to determine genetic sex by karyotyping: parents should be reassured as to the baby’s sex (never ‘in between’). Blood levels of adrenal hormones are measured to obtain a precise diagnosis. Traditionally, doctors have advised parents to ‘choose’ their child’s gender on the basis of discussing the likely condition of the genitalia after puberty. Thus, where the phallus is likely to be inadequate as a male organ, it may be preferred to rear the child as female. Surgery is usually advised in the ?rst two years to deal with clitoromegaly but parent/ patient pressure groups, especially in the US, have declared it wrong to consider surgery until the children are competent to make their own decision.

Other treatment requires replacement of the missing hormones which, if started early, may lead to normal sexual development. There is still controversy surrounding the ethics of gender reassignment.

See www.baps.org.uk... adrenogenital syndrome

Liquorice Root

The universal herb. Sweet root. Glycyrrhiza glabra L. Shredded or powdered dried root. Long history for strength and long life in Chinese medicine. Sweet of the Pharoahs of Ancient Egypt. Carried by armies of Alexander to allay thirst and as a medicine.

Constituents: volatile oil, coumarins, chalcones, triterpenes, flavonoids.

Action: demulcent expectorant, glycogenconservor, anti-inflammatory, mild laxative. Adrenal restorative (has glycosides remarkably similar to body steroids). ACTH-like activity on adrenal cortex (Simon Mills). Female hormone properties (Science Digest). Regulates salt and water metabolism (Medicina, Moscow, 1965). Anti-stress. Anti-ulcer. Antiviral. Increases gastric juices up to 25 per cent, without altering pH. Aldosterone-like effect. Liver protective. Anti-depressive.

Use s. Adrenal insufficiency – sodium-retention properties suitable for Addison’s disease. Hypoglycaemia. Peptic ulcer – reduces gastric juice secretion. Inflamed stomach. Mouth ulcer. Duodenal ulcer. Respiratory infections: dry cough, hoarseness, bronchitis, lung troubles, catarrh. Tuberculosis (Chinese traditional). In the absence of more effective remedies of value in food poisoning. To prevent urinary tract infections.

Combinations: with Iceland Moss for wasting and cachexia to nourish and increase weight; with Lobelia for asthma and bronchitis: with Raspberry leaves for the menopause; with Comfrey for dental caries.

“Liquorice is recorded as a cancer remedy in many countries.” (J.L. Hartwell, Lloydia, 33, 97. 1970) Preparations. Average dose: 1-5 grams. Thrice daily before meals.

Decoction: half-1 teaspoon to each cup water, simmer 15 minutes. Half-1 cup.

Liquid Extract: 1:1. Dose: 2-5ml.

Sticks: for chewing.

Powdered root: 750mg (three 00 capsules or half a teaspoon).

Diet: Pontefract cakes – use in kitchen for adrenal failure; because of their sodium-retaining properties may be taken as sweets without added sugar. Low salt when taken.

Contra-indicated: In pregnancy, cirrhosis (liver) and in the presence of digitalis.

Note: If over-consumed may result in low potassium levels, high blood pressure and falls in renin and aldosterone. Where taken for a long period, increase intake of potassium-rich foods. May cause fluid retention of face and ankles which could be tolerated while primary disorder is being healed. ... liquorice root

Hyperaldosteronism

A metabolic disorder caused by an overproduction of the hormone aldosterone by the adrenal glands (see aldosteronism).... hyperaldosteronism

Hypoaldosteronism

A rare deficiency of the hormone aldosterone, which is produced by the adrenal glands. The condition may be caused by damage or disease affecting the adrenal glands. It may produce weakness, and is treated by the drug fludrocortisone.... hypoaldosteronism

Acth

The common abbreviation for adrenocorticotrophic hormone (also called corticotrophin). is produced by the anterior pituitary gland and stimulates the adrenal cortex (outer layer of the adrenal glands) to release various corticosteroid hormones, most importantly hydrocortisone (cortisol) but also aldosterone and androgen hormones.

production is controlled by a feedback mechanism involving both the hypothalamus and the level of hydrocortisone in the blood. levels increase in response to stress, emotion, injury, infection, burns, surgery, and decreased blood pressure.

A tumour of the pituitary gland can cause excessive production which leads to overproduction of hydrocortisone by the adrenal cortex, resulting in Cushing’s syndrome. Insufficient production results in decreased production of hydrocortisone, causing low blood pressure. Synthetic is occasionally given by injection to treat arthritis or allergy.... acth

Adrenal Gland Disorders

A range of uncommon but sometimes serious disorders due to deficient or excessive production of hormones by one or both of the adrenal glands.

A genetic defect causes congenital adrenal hyperplasia, in which the adrenal cortex is unable to make sufficient hydrocortisone and aldosterone, and androgens are produced in excess. In adrenal failure, there is also deficient production of hormones by the adrenal cortex; if due to disease of the adrenal glands, it is called Addison’s disease. Adrenal tumours are rare and generally lead to excess hormone production.

In many cases, disturbed activity of the adrenal glands is caused, not by disease of the glands themselves, but by an increase or decrease in the blood level of hormones that influence the action of the adrenal glands. For example, hydrocortisone production by the adrenal cortex is controlled by ACTH, which is secreted by the pituitary gland. Pituitary disorders can disrupt production of hydrocortisone.... adrenal gland disorders

Congenital Adrenal Hyperplasia

a family of autosomal *recessive genetic disorders causing decreased activity of any of the enzymes involved in the synthesis of *cortisol from *cholesterol. The most commonly affected enzymes are 21-hydroxylase and 11-hydroxylase, and each enzyme deficiency can itself be due to a variety of genetic mutations. The clinical manifestations depend on which enzyme is affected and the resultant deficiencies and build-up products produced. The most serious consequence is adrenal crisis and/or severe salt wasting due to lack of cortisol and/or aldosterone, which may prove fatal if undiagnosed. The condition is often easier to spot at birth in females, who may have indeterminate genitalia due to high levels of *testosterone in utero. Adrenal hyperplasia occurs due to excessive stimulation of the glands by *ACTH (adrenocorticotrophic hormone) in response to the resultant cortisol deficiency of these conditions. Less complete deficiencies of the enzymes concerned may present for the first time in young women after puberty, with signs of androgen excess and menstrual irregularity mimicking *polycystic ovary syndrome.... congenital adrenal hyperplasia

Corticosteroid

(corticoid) n. any steroid hormone synthesized by the adrenal cortex. There are two main groups of corticosteroids. The glucocorticoids (e.g. *cortisol, *cortisone, and corticosterone) are essential for the utilization of carbohydrate, fat, and protein by the body and for a normal response to stress. Naturally occurring and synthetic glucocorticoids have very powerful anti-inflammatory effects and are used to treat conditions that involve inflammation. The mineralocorticoids (e.g. *aldosterone) are necessary for the regulation of salt and water balance.... corticosteroid

Enalapril

n. a drug used in the treatment of high blood pressure (hypertension) and heart failure. It inhibits the action of angiotensin (see ACE inhibitor), which results in decreased vasopressor (blood-vessel constricting) activity and decreased aldosterone secretion. Side-effects can include a persistent dry cough, a drastic fall in blood pressure, headache, dizziness, fatigue, and diarrhoea.... enalapril

Fludrocortisone

n. a synthetic mineralocorticoid (see corticosteroid) used to treat disorders of the adrenal glands marked by deficient production of aldosterone. Side-effects include muscle weakness, bone disorders, digestive and skin disorders, and fluid retention.... fludrocortisone

Gordon’s Syndrome

(pseudohypoaldosteronism type II, chloride shunt syndrome) an autosomal *dominant condition associated with increased chloride absorption in the distal tubule leading to a syndrome of mild volume expansion, hypertension, and metabolic acidosis with otherwise normal renal function. Plasma *renin and *aldosterone are suppressed as a result of the volume expansion. Other features can include short stature, intellectual impairment, muscle weakness, and renal stones.... gordon’s syndrome

Metyrapone

n. a drug that interferes with the production of the hormones *cortisol and *aldosterone and is used in the diagnosis and treatment of *Cushing’s syndrome. Side-effects may include nausea, vomiting, low blood pressure, and allergic reactions.... metyrapone

Juxtaglomerular Apparatus

(JGA) a microscopic structure within the kidney that is important in regulating blood pressure, body fluid, and electrolytes. It is situated in each nephron, between the afferent arteriole of the glomerulus and the returning distal convoluted tubule of the same nephron. The JGA consists of specialized cells within the distal tubule (the macula densa), which detect the amount of sodium chloride passing through the tubule and can secrete locally acting vasoconstrictor substances that act on the associated afferent arteriole to induce a reduction in filtration pressure (tubuloglomerular feedback). Modified cells within the afferent arterioles secrete *renin in response to a fall in perfusion pressure or feedback from the macula densa and form a central role in the renin-*angiotensin-aldosterone axis. Mesangial cells support and connect the macula densa and the specialized cells in the afferent arteriole and have sympathetic innervation, facilitating the renin response to sympathetic nervous stimulation.... juxtaglomerular apparatus

Liddle’s Syndrome

a rare autosomal *dominant condition characterized by hypertension associated with hypokalaemia, metabolic alkalosis, and low levels of plasma *renin and *aldosterone. The hypertension often starts in infancy and is due to excess resorption of sodium and excretion of potassium by the renal tubules. The syndrome is caused by a single genetic mutation on chromosome 16, which results in dysregulation of a sodium channel in the distal convoluted tubule. Treatment is with a low salt diet and a potassium-sparing diuretic that directly blocks the sodium channel, such as amiloride or triamterene. [G. G. Liddle (1921–89), US endocrinologist]... liddle’s syndrome

Renal Tubular Acidosis

(RTA) metabolic acidosis due to failure of the kidney to excrete acid into the urine. Three types of RTA are recognized. Type 1 (distal RTA) results from a reduction in net acid secretion in the distal convoluted tubule (see nephron) and an inability to acidify the urine. Hypokalaemia is often present and may be severe. The condition can be either genetically determined or, more commonly, the result of systemic disease (e.g. autoimmune disorders) or drugs (e.g. amphotericin). Type II (proximal RTA) is due to a lowered threshold for bicarbonate reabsorption; eventually a steady state is established with a low serum bicarbonate but capacity to acidify the urine. Hypokalaemia is present due to *aldosteronism caused by the increased delivery of sodium to the distal tubule. Proximal RTA usually occurs as part of more widespread proximal tubule dysfunction with the *Fanconi syndrome. Type IV RTA results from impaired excretion of both acid and potassium and results in acidosis with hyperkalaemia. It is most commonly seen with aldosterone deficiency. This may be isolated, especially in diabetics, or it may be induced by drugs (angiotensin II antagonists or ACE inhibitors).... renal tubular acidosis

Renovascular Hypertension

disease affecting the arterial supply to the kidneys, leading to ischaemia and resultant stimulation of the renin-*angiotensin-aldosterone axis. In the major vessels, the most common cause is atheromatous plaque disease. Other causes are fibromuscular dysplasia and *Takayasu’s disease.... renovascular hypertension



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