الفهرس 
acknowledgmentOnly 14 pages are availabe for public view
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Abstract
The catecholamines nora^renaline , adrenaline and are 3,d dihydroxyderivatives of phenylethylanine . They are widely distributed throughout the animal kingdom, moat often in nerve cells.
Catecholamines ere found in the peripheral sympa¬thetic nervous system ^ ’ t the adrenal medulla^ and are une qually distributed in different areas of the central nervous
Noradrenaline is highly localized in peripheral
post-ganglionic sympathetic nerves. It is released from
(2}
sympathetic nerve terminals as a neuro transmitter^ and
exert most of its effects locally on postsyn&ptic cells.
Adrenaline functions mainly as a horroone being released into the general circulation primarily from the adrenal medulla. Email amounts of adrenaline have been found
in mammalian brain and heart.
A third catecholamine , dopamine, serves aa a
precursor of noradrenaline and adrenaline in both peripheral and central nervous system. Its most important function,
however, may be in the brain, where high concentrations are found in the gtriatum . E 5 ’ 6’
Cateeholamineg influence the actions of a wide
variety of tissues such as vascular smooth nuscle , adipose
/ p> issue, liver, heart and brain.’ In many cases they act by
causing an increase in the activity or amount of a specific