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ENDOCRINE PHYSIOLOGY    Adrenal Medulla

CH/-CH-COOH

ganglia

CH₇-CH₂-NH >

IJrinary excretion of metabolites

i) ĆH, OH

I /T, Conversion stimulated by cortisol

Figurę 8.17 Function of the Adrenal Medulla

The adrenal medulla produces epinephrine and norepinephrine. The medullary cells actualfy are the postganglionic elemenls ot the sym-pathetic division ot the autonomie nervous sys>tem. but as endocrine cells, they release epinephrint: and norepinephrine into the blood rather than into a synaptic delt. Epinephrine accounts for about 70% to 80% of the mcdulldry secretions. The relative magnitude and effeets ot epinephrine and norepinephrine are illustrated.

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