Time-course of the effect of alpha-methyl-p-tyrosine on ACTH secretion.
250 mg/kg i.p. of the methyl ester of alpha-methyl-p-tyrosine (alpha-MpT) produced a rapid increase (by 1 h) in immunoreactive plasma ACTH, whereas the hypothalamic norepinephrine (NE) concentration and plasma corticosterone (B) changed significantly only 6 h after the administration of the inhibitor. These data suggest that the norepinephrinergic inhibitory tonus of CRF-ACTH secretion depends on the availability of a rapidly utilized pool of transmitter, affected in a very short time by alpha-MpT.
D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000818:Animals; D003345:Corticosterone / Q000378:metabolism; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism*; D008297:Male; D008781:Methyltyrosines / Q000494:pharmacology*; D009638:Norepinephrine / Q000378:metabolism; D051381:Rats; D013997:Time Factors
D008781:Methyltyrosines; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D003345:Corticosterone; D009638:Norepinephrine