Effect of estrogen on the response of thyroid stimulating hormone to substance P in rats.
The role of substance P (SP) in the control of thyroid stimulating hormone (TSH) release and the influence of gonadal steroid were investigated. Intravenous administration of SP failed to alter plasma levels of TSH in ovariectomized (OVX) rats, whereas SP induced a significant increase in plasma TSH in estradiol benzoate-primed (Eb-primed) OVX rats (P less than 0.001). Further, intravenously administered SP did not affect the plasma TSH concentration in normal male rats, but significantly increased it in Eb-primed castrated male rats (P less than 0.01). These data suggest possible roles for SP at the level of the hypothalamus and/or the pituitary gland in stimulating TSH secretion under the influence of estrogen.
Arisawa
M
M
Department of Obstetrics and Gynecology, School of Medicine, Keio University.
Makino
T
T
McCann
S M
SM
Iizuka
R
R
D000818:Animals; D002369:Castration; D004958:Estradiol / Q000494:pharmacology; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D007275:Injections, Intravenous; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013373:Substance P / Q000008:administration & dosage / Q000502:physiology*; D013972:Thyrotropin / Q000378:metabolism*
D004967:Estrogens; D013373:Substance P; D004958:Estradiol; D013972:Thyrotropin