A neurotransmitter found in the brain and around some blood vessels. It helps control body movements: a deficiency of dopamine in the basal ganglia (groups of nerve cells deep in the brain) causes Parkinson’s disease.
Synthetic dopamine is injected as an emergency treatment for shock caused by a myocardial infarction (heart attack) or septicaemia (blood infection) and as a treatment for severe heart failure.
Dopamine is one of the CATECHOLAMINES and a precursor of NORADRENALINE. Its highest concentration is in that portion of the brain known as the basal nuclei (see BRAIN) where its function is to convey inhibitory in?uences to the extrapyramidal system. There is good evidence that dopamine de?ciency is one of the causative factors in PARKINSONISM.
Dopamine is given by intravenous infusion as treatment for cardiogenic shock in cardiac infarction or cardiac surgery.
n. a *catecholamine derived from dopa that functions as a *neurotransmitter, acting on specific dopamine receptors and also on adrenoceptors throughout the body, especially in the *limbic system and *extrapyramidal system of the brain as well as the arteries and the heart. It also stimulates the release of noradrenaline from nerve endings. The effects vary with location and concentration. Dopamine is used in carefully controlled dosage to increase the strength of contraction of the heart in heart failure, shock, severe trauma, and septicaemia. Possible side-effects include unduly rapid or irregular heartbeat, nausea, vomiting, breathlessness, angina pectoris, and kidney damage.
Certain drugs (dopamine receptor agonists) have an effect on the body similar to that of dopamine. They include *apomorphine, *pergolide, *ropinirole, *cabergoline, and pramipexole and are used to treat *parkinsonism. Drugs that compete with dopamine to occupy and block the dopamine receptor sites in the body are known as dopamine receptor antagonists. They include some *antipsychotic drugs (e.g. the phenothiazines and *butyrophenones) and certain drugs (e.g. *domperidone and *metoclopramide) used to treat nausea and vomiting.
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