ENDOCRINE SYSTEM
ADRENAL
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Hydroxlation
|
|
|
Decarboxlation
|
|
|
N-methylation
|
|
|
None of the above
|
Detailed explanation-1: -The end product of epinephrine and norepinephrine is vanillylmandelic acid (VMA) which is excreted in the urine. Dopamine catabolism leads to the production of homovanillic acid (HVA).
Detailed explanation-2: -All catecholamines are synthesized from the amino acid l-tyrosine according to the following sequence: tyrosine → dopa (dihydroxyphenylalanine) → dopamine → norepinephrine (noradrenaline) → epinephrine (adrenaline).
Detailed explanation-3: -Vanillic acid (VMA) is the major end product of human norepinephrine and epinephrine metabolism (64).
Detailed explanation-4: -In dopaminergic neurons of the central nervous system, dopamine serves as the end product neurotransmitter. Large amounts of dopamine are produced as an end product of catecholamine synthesis in peripheral non-neuronal cells of the gastrointestinal tract and kidneys.