Gonadectomy eliminates endothelium-dependent diethylstilbestrol-induced relaxant effect in rat aorta.
The effects of gender and castration of rats on diethylstilbestrol-induced, endothelium-dependent and endothelium-independent relaxation in rat aorta strips were studied. For this, male and female control and castrated rats were used. Diethylstilbestrol elicited a concentration-dependent (1-30 micromol/l) relaxation of isolated rat aorta. The effect was significantly higher in the presence of endothelium in aorta strips of the control group and also in female as compared with male rats. This effect is NO-dependent, since it is inhibited by N(G)-methyl-L-arginine. Castration of the rats suppressed the endothelium-dependent relaxation, and it was similar to that induced in the absence of endothelium. Acetylcholine-induced relaxation was not suppressed by castration. The acetylcholine-induced relaxation was decreased in aorta strips previously relaxed by diethylstilbestrol. There are no gender differences in the diethylstilbestrol-induced, endothelium-independent component of the relaxation, nor is it modified by the hormonal environment. Therefore, diethylstilbestrol-induced, endothelium-dependent relaxation in rat aorta strips is modulated by the hormonal status of the rats.
Martínez
Carmen
C
Departamento de Medicina, Facultad de Medicina, Oviedo, Spain.
López
Covadonga
C
Hidalgo
Agustín
A
Sánchez
Manuel
M
García de Boto
María José
MJ
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects* / Q000503:physiopathology; D004054:Diethylstilbestrol / Q000494:pharmacology*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology; D004968:Estrogens, Non-Steroidal / Q000494:pharmacology*; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000503:physiopathology; D009919:Orchiectomy; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar; D011960:Receptors, Estrogen / Q000037:antagonists & inhibitors; D012737:Sex Factors; D014665:Vasodilator Agents / Q000494:pharmacology
D004968:Estrogens, Non-Steroidal; D011960:Receptors, Estrogen; D014665:Vasodilator Agents; D004054:Diethylstilbestrol; D000109:Acetylcholine