The influence of alpha-fluoromethylhistidine and histamine receptor antagonists on the beta-endorphin-induced corticosterone response.
Involvement of a central histaminergic mechanism in the stimulating effect of beta-endorphin (beta-End) on the pituitary-adrenocortical activity, measured indirectly through corticosterone secretion, was investigated in conscious rats. The rise in serum corticosterone levels, induced by beta-End injected intraventricularly (icv) was considerably impaired by pretreatment with naltrexone, an opioid receptor antagonist. The stimulating effect of beta-End was almost totally suppressed by a prior icv administration of mepyramine, a histamine H1-receptor antagonist, and also considerably reduced by pretreatment with cimetidine, an H2-receptor antagonist. The strongest suppression, by 83%; of the beta-End-induced corticosterone response was evoked by a prior administration of alpha-fluoromethylhistidine, an inhibitor of neuronal histamine synthesis in the brain. These results indicate that both the brain neuronal histamine and central histamine H1- and H2-receptors are considerably involved in the beta-endorphin-induced stimulation of the pituitary-adrenocortical activity.
Turoń
M
M
Institute of Pharmacology, Polish Academy of Sciences, Kraków.
Tytoń
J
J
Bugajski
J
J
D000818:Animals; D001921:Brain / Q000378:metabolism; D003345:Corticosterone / Q000097:blood / Q000378:metabolism*; D006632:Histamine / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000494:pharmacology; D006633:Histamine Antagonists / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D009271:Naltrexone / Q000494:pharmacology; D010913:Pituitary-Adrenal System / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D011968:Receptors, Histamine / Q000502:physiology; D001615:beta-Endorphin / Q000008:administration & dosage / Q000494:pharmacology*
D006633:Histamine Antagonists; D011968:Receptors, Histamine; D009271:Naltrexone; D001615:beta-Endorphin; C054284:alpha-fluoromethylhistamine; D006632:Histamine; D003345:Corticosterone