Chromaffin cells of the adrenal medulla are innervated by the splanchnic nerve and secrete adrenaline (epinephrine), noradrenaline (norepinephrine), some dopamine, enkephalin and enkephalin-containing peptides, and a few other hormones into the blood stream.
The secreted adrenaline and noradrenaline play an important role in the sympathetic nervous system response, commonly called the fight-or-flight response.
The enkephalins and enkephalin-containing peptides are related to, but distinct from endogenous peptides named endorphins (which are secreted from the pituitary); all of these peptides bind to opioid receptors and produce analgesic (and other) responses.
The hormones are secreted from chromaffin granules; this is where the enzyme dopamine β-hydroxylase catalyses the conversion of dopamine to noradrenaline.
 Distinct N and E cell forms exist (also Na and A cells in British nomenclature - noradrenaline and adrenaline); the former produce norepinephrine, the latter arise out of N cells through interaction with glucocorticoids, and convert norepinephrine into epinephrine.
Chromaffin cells of the adrenal medulla are innervated by the splanchnic nerve and secrete adrenaline (epinephrine), noradrenaline (norepinephrine), some dopamine, enkephalin and enkephalin-containing peptides, and a few other hormones into the blood stream. The secreted adrenaline and noradrenaline play an important role in the sympathetic nervous system response, commonly called the fight-or-flight response. The enkephalins and enkephalin-containing peptides are related to, but distinct from endogenous peptides named endorphins (which are secreted from the pituitary); all of these peptides bind to opioid receptors and produce analgesic (and other) responses. The hormones are secreted from chromaffin granules; this is where the enzyme dopamine β-hydroxylase catalyses the conversion of dopamine to noradrenaline.  Distinct N and E cell forms exist (also Na and A cells in British nomenclature - noradrenaline and adrenaline); the former produce norepinephrine, the latter arise out of N cells through interaction with glucocorticoids, and convert norepinephrine into epinephrine.
Chromaffin cell