(Greek) Two together Synah
The term applied to the anatomical relation of one NEURON(E) (nerve cell) with another which is e?ected at various points by contact of their branching processes. The two neurons do not come directly into contact, but the release of a chemical NEUROTRANSMITTER by one neuronal AXON is followed by this chemical travelling across the synapse and ?ring o? the signal along another nerve. A signal can be sent across a synapse in one direction only, from presynaptic or postsynaptic membranes. Synapses are divided into excitatory and inhibitory types. When a neurotransmitter travels across an excitatory synapse it usually provokes the receptor neuron into initiating an electrical impulse. Inhibitory synapses cool down the excitation of the adjacent neurons. Drugs that in?uence the NERVOUS SYSTEM usually do so by affecting the release or modi?cation of the neurotransmitters passing across the synapse.... synapse
A condition in which stimulation of one of the senses (by a sound, for example) produces an additional response, such as the appearance of a colour in addition to the normal perception associated with that stimulus.... synaesthesia
tests used to assess the ability of the adrenal cortex to produce cortisol. Serum cortisol is measured before and then 30 minutes (or 5 hours) after an intramuscular injection of 250 ?g (or 1 mg) tetracosactide (Synacthen), an analogue of *ACTH. The adrenal glands are considered to be inadequate if there is a low baseline concentration of cortisol or the rise is less than a certain predefined amount.... synacthen tests
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