MK-771 enhances the turnover of norepinephrine in brain.
Single injection of MK-771, an analog of thyrotropin-releasing hormone (10 mg/kg) increased the soluble tyrosine hydroxylase activity in striatum and olfactory tubercles by 22% and 31%. The endogenous levels of norepinephrine in olfactory tubercles, striatum, hypothalamus, mid-brain, pons medulla and cerebral cortex remained unchanged; in hippocampus, it was lowered to 71% of controls. Furthermore, the concentration of 3-methoxy-4-hydroxy-phenylethylene glycol was enhanced by 33%. Data suggest that MK-771 increases the synthesis and release of norepinephrine and that MK-771 elicits its CNS stimulant action partly by augmenting the turnover of this biogenic amine.
D000818:Animals; D001921:Brain / Q000378:metabolism*; D003342:Corpus Striatum / Q000378:metabolism; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D009830:Olfactory Bulb / Q000201:enzymology; D051381:Rats; D013268:Stimulation, Chemical; D053778:Thiazolidines; D013973:Thyrotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D053778:Thiazolidines; D013973:Thyrotropin-Releasing Hormone; C021597:pyro(l-alpha-aminoadipyl)-L-histidyl-L-thiazolidine-4-carboxamide; D014446:Tyrosine 3-Monooxygenase; D009638:Norepinephrine