Melatonin, 5-methoxytryptamine and some of their analogs as cyclo-oxygenase inhibitors in rat medial basal hypothalamus.
Melatonin, and its analogs 6-chloro- and 6-fluoromelatonin inhibited in a dose-dependent way (10(-8)-10(-5) M) labeled prostaglandin (PG) E2, PGF2 alpha, thromboxane (Tx) B2 and 6-keto-PGF1 alpha production from [14C]arachidonate by rat medial basal hypothalamus (MBH). 5-Methoxytryptamine also depressed arachidonate metabolism; at 10(-8) M concentrations the effect of 5-methoxytryptamine on PGE2, PGF2 alpha and TxB2 synthesis (93-96% inhibition), and 6-keto-PGF1 alpha (75% inhibition) was greater than that observed for melatonin (51-56% and 44% inhibition, respectively). Neither 6-hydroxymelatonin nor serotonin affected MBH cyclo-oxygenase pathway in vitro.
D008735:5-Methoxytryptamine / Q000031:analogs & derivatives / Q000494:pharmacology*; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D016861:Cyclooxygenase Inhibitors; D007033:Hypothalamus, Middle / Q000187:drug effects / Q000201:enzymology*; D066298:In Vitro Techniques; D008297:Male; D008550:Melatonin / Q000031:analogs & derivatives / Q000494:pharmacology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D011453:Prostaglandins / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014363:Tryptamines / Q000494:pharmacology*
D001095:Arachidonic Acids; D016861:Cyclooxygenase Inhibitors; D011453:Prostaglandins; D014363:Tryptamines; D016718:Arachidonic Acid; D008735:5-Methoxytryptamine; D011451:Prostaglandin-Endoperoxide Synthases; D008550:Melatonin