des-Tyr1-gamma-endorphin and haloperidol increase pineal gland melatonin levels in rats.
The effect of subcutaneously injected DT gamma E (beta-endorphin, (beta E)2-17) on the pineal melatonin level was compared with that of closely related peptides and the neuroleptic drug haloperidol. As found previously, DT gamma E (3 ng/rat and 300 ng/rat) increased the melatonin levels. Similar doses of DT alpha E (beta E 2-16), DT beta E (beta E 2-31), gamma E (beta E 1-17), alpha E (beta E 1-16) and beta E failed to significantly change the melatonin levels in both the dark and the light phase. Haloperidol in a dose of 300 ng/rat exhibited a similar effect as DT gamma E.
D000818:Animals; D003624:Darkness; D004723:Endorphins / Q000494:pharmacology*; D006220:Haloperidol / Q000494:pharmacology*; D008027:Light; D008297:Male; D008550:Melatonin / Q000378:metabolism*; D010446:Peptide Fragments / Q000494:pharmacology*; D010870:Pineal Gland / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D004723:Endorphins; D010446:Peptide Fragments; C018903:gamma-endorphin, des-Tyr(1)-; D006220:Haloperidol; D008550:Melatonin