Neurosecretion of human hypothalamic immunoreactive beta-endorphin: in vitro regulation by dopamine.
An in vitro perifusion system was used to investigate immunoreactive beta-endorphin (beta-END-I) release from adult human hypothalami in response to dopamine (DA) and the DA receptor antagonist haloperidol (HAL). Administration of a 1 microM pulse of DA consistently elicited a mean (+/- SE) 88 +/- 9% increase (p less than 0.05, n = 5) in beta-END-I release, whereas 1 microM HAL had no effect. Administration of 1 microM DA during three perifusions in which 1 microM HAL was added to the medium failed to alter basal beta-END-I release. In contrast, DA did evoke an acute 230 +/- 31% increase (p less than 0.05) in beta-END-I release during three matching perifusions with medium containing the alpha-adrenergic antagonist phentolamine. These studies demonstrate that DA can stimulate in vitro release of beta-END-I from the adult human hypothalamus by a DA receptor mediated mechanism.
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004298:Dopamine / Q000502:physiology*; D004723:Endorphins / Q000378:metabolism*; D005260:Female; D006220:Haloperidol / Q000494:pharmacology; D006801:Humans; D007033:Hypothalamus, Middle / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010477:Perfusion; D010646:Phentolamine / Q000494:pharmacology; D011954:Receptors, Dopamine / Q000502:physiology; D001615:beta-Endorphin
D004723:Endorphins; D011954:Receptors, Dopamine; D001615:beta-Endorphin; D006220:Haloperidol; D004298:Dopamine; D010646:Phentolamine