The effects of des-enkephalin-gamma-endorphin and des-Tyr1-a-endorphin on regional serotonin metabolism in rat brain.
Des-enkephalin-gamma-endorphin (beta-endorphin6-17; DE gamma E) causes a significant reduction of the serotonin concentration of the raphe area of the mesencephalon and of the dorsal hippocampus of the rat. DE gamma E does not, however, alter the pargyline-induced accumulation of serotonin in either of these two brain regions or in the mediobasal hypothalamus. Des-Tyr1-a-endorphin (beta-endorphin2-16; DTaE), on the other hand, inhibits the accumulation of serotonin following MAO-inhibition by pargyline in all 3 brain regions, while, in addition to causing a transient reduction in the serotonin concentration of the raphe area, it decreases the serotonin concentration of the mediobasal hypothalamus. These results indicate that DE gamma E and DTaE, which have been shown to exert opposite effects on behavior in various behavioral tests, both affect regional serotonin metabolism in rat brain and that they do so differently.
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects; D001921:Brain / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004723:Endorphins / Q000494:pharmacology*; D004745:Enkephalins / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects; D007033:Hypothalamus, Middle / Q000187:drug effects; D008297:Male; D008636:Mesencephalon / Q000187:drug effects; D010446:Peptide Fragments / Q000494:pharmacology*; D011903:Raphe Nuclei / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*; D001615:beta-Endorphin
D004723:Endorphins; D004745:Enkephalins; D010446:Peptide Fragments; D012701:Serotonin; D001615:beta-Endorphin; C018903:gamma-endorphin, des-Tyr(1)-; C033558:des-enkephalin-gamma-endorphin