Effects of phenolic monoamines on release of luteinizing hormone stimulated by gonadotropin-releasing hormone and on plasma adrenocorticotropic hormone, norepinephrine, and cortisol concentrations in wethers.
Eighteen Suffolk and Suffolk x Hampshire wethers (56.3 +/- 1.3 kg) were used to determine the effects of naturally occurring amines, N-methyl-beta-phenethylamine (NMP) and tyramine (T), on plasma cortisol, norepinephrine (NE), ACTH, and GnRH-stimulated LH concentrations. In each experiment, wethers were assigned randomly to treatments with six replicates/treatment. In Exp. 1, treatments consisted of saline, 2 mg of NMP/kg BW (NMP2), or 4 mg of NMP/kg BW (NMP4). In Exp. 2, treatments consisted of saline, 4 mg of NMP/kg BW (N), or 2 mg of NMP + 4 mg of T/kg BW (NT). All treatments were given via indwelling jugular catheters in single doses of 2 mL. In Exp. 1, no effects of time after treatment on response were detected. The NMP2 wethers had lower cortisol and LH peak amplitudes (PKAMP) than other wethers (P < .03 and .05, respectively). Time to peak (PKT) concentration of NE was significantly shorter in NMP4-treated wethers (P < .004). In Exp. 2, significant interactions between time and treatment were detected for cortisol, NE, and LH. Cortisol and NE concentrations were increased (P < .0001 and P < .03, respectively) in N- and NT-treated wethers compared with controls, whereas LH was reduced (P < .003). The N and NT treatments increased cortisol PKT, peak height (PKHT), and PKAMP above that of controls (P < .02, < .006, and < .02, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
Forbes
T D
TD
Texas Agricultural Experiment Station, Uvalde 78801.
Carpenter
B B
BB
Randel
R D
RD
Tolleson
D R
DR
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000704:Analysis of Variance; D000818:Animals; D007987:Gonadotropin-Releasing Hormone / Q000502:physiology; D006854:Hydrocortisone / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D008694:Methamphetamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D009638:Norepinephrine / Q000097:blood; D012756:Sheep / Q000097:blood / Q000378:metabolism*; D014439:Tyramine / Q000494:pharmacology*
C027141:N-methylphenethylamine; D007987:Gonadotropin-Releasing Hormone; D008694:Methamphetamine; D000324:Adrenocorticotropic Hormone; D007986:Luteinizing Hormone; D006854:Hydrocortisone; D009638:Norepinephrine; D014439:Tyramine