Scopolamine effects on the pressor response to thyrotropin-releasing hormone in humans.
Thyrotropin-releasing hormone (TRH) produces a marked pressor effect, which may be mediated by central cholinergic neurons, which in turn enhance sympathetic nervous system activity. In this study, 22 subjects (10 patients with Alzheimer's disease and 12 elderly controls) were administered IV scopolamine or placebo prior to administration of IV high-dose TRH (0.5 mg/kg). Systolic blood pressure was less on the day scopolamine was administered prior to TRH administration, as compared with placebo (F[1,20] = 6.12, p < 0.02). Results indicate that the pressor effect of TRH is attenuated by scopolamine, indicating a role of the cholinergic system in this response in humans.
Molchan
S E
SE
Section on Geriatric Psychopharmacology, National Institute of Mental Health, Bethesda, MD 20892.
Hill
J L
JL
Minichiello
M
M
Vitiello
B
B
Sunderland
T
T
D000368:Aged; D000544:Alzheimer Disease / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008734:Methoxyhydroxyphenylglycol / Q000097:blood; D008875:Middle Aged; D012601:Scopolamine / Q000494:pharmacology*; D013973:Thyrotropin-Releasing Hormone / Q000502:physiology*
D008734:Methoxyhydroxyphenylglycol; D013973:Thyrotropin-Releasing Hormone; D012601:Scopolamine