Epinephrine or adrenalin is a peripheral hormone released by the adrenomedullary A cell which is an APUD cell. This hormone (monamine) is under the control of the autonomic nervous system and it is mainly its secretion that causes the phenomena of flight flight fright which prepares an organism for a stressful situation. This sympathetico-adrenal system was evolved in the vertebrate subphylum to deal with situations that cause distress to the organism. The sympathetico-adrenal system is well developed in the cyclostomes.

            Although it is not thought to be present in the central nervous system, its effects on behaviour is probably more pronounced than all other monoamines. The following will prove the point.

a)                                                      Blockage of the central mechanism of FFF by propanolol a β-blocker is the main cause of relief of anxiety symptoms in anxiety states or neurosis.

b)                                                      As a result of the above, there is obviously a central connection which causes peripheral release of adrenalin.

c)                                                      Its derangement is mainly the cause of minipsychiatric ailments like anxiety neurosis, phobic states and psychosomatic illnesses.

d)                                                      It is the main peripheral method of modulation in autonomic nervous system tuning concept proposed by Gellhorn and Kiely and propagated in anthropological psychology by Lex.

e)                                                      It is the major direct link of the Diffuse Neuroendocrine System of Pearse and his associates and the peripheral nervous system








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