title: Gonadectomy eliminates endothelium-dependent diethylstilbestrol-induced relaxant effect in rat aorta.
abstract: 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.
authors.affiliation: Departamento de Medicina, Facultad de Medicina, Oviedo, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Martínez
authors.forename: Covadonga
authors.initials: C
authors.lastname: López
authors.forename: Agustín
authors.initials: A
authors.lastname: Hidalgo
authors.forename: Manuel
authors.initials: M
authors.lastname: Sánchez
authors.forename: María José
authors.initials: MJ
authors.lastname: García de Boto
mesh_terms: 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
chemical_list: D004968:Estrogens, Non-Steroidal; D011960:Receptors, Estrogen; D014665:Vasodilator Agents; D004054:Diethylstilbestrol; D000109:Acetylcholine