title: Evidence that chronic administration of 17β-oestradiol decreases the vasopressor responses to adrenergic system stimulation in streptozotocin-diabetic female rats.
abstract: In vitro studies have indicated that 17β-oestradiol exerts beneficial effects on the cardiovascular system by activating the nitric oxide pathway. However, these effects have not been demonstrated in vivo in the systemic vasculature of rats made diabetic through streptozotocin induction. Therefore, the goal of this study was to determine the effect of 17β-oestradiol on vasopressor responses induced by sympathetic stimulation or i.v. injections of noradrenaline, methoxamine and B-HT 933 in sham-operated or ovariectomised, diabetic or non-diabetic female rats. Thus, rats were ovariectomised or sham-operated for this experiment. One week later, the animals were treated with streptozotocin (60mg/kg, i.p.) or its vehicle. Two weeks later, these rats were treated daily with 17β-oestradiol (10μg/kg, s.c.) or its vehicle for five weeks. Next, under anaesthesia, the animals were pithed and prepared for blood pressure and heart rate measurements. 17β-oestradiol failed to modify the vasopressor responses to (i) sympathetic stimulation, noradrenaline, methoxamine or B-HT 933 in sham-operated non-diabetic rats; (ii) sympathetic stimulation or B-HT 933 in sham-operated diabetic rats; (iii) noradrenaline or methoxamine in ovariectomised non-diabetic rats. In contrast, 17β-oestradiol significantly decreased the vasopressor responses to (i) noradrenaline and methoxamine in sham-operated diabetic rats; (ii) sympathetic stimulation or B-HT 933 in ovariectomised non-diabetic rats; and (iii) sympathetic stimulation, noradrenaline, methoxamine or B-HT 933 in ovariectomised diabetic rats. These results suggest that chronic administration of 17β-oestradiol decreases the vasopressor responses to adrenergic system stimulation in streptozotocin-induced diabetic rats. This report describes the first in vivo study reporting this effect of 17β-oestradiol in diabetes.
authors: Departamento de Farmacobiología, Cinvestav-Coapa, Czda. de los Tenorios 235, Col. Granjas Coapa, Deleg. Tlalpan, C.P. 14330 México D.F., Mexico.
authors: Selene J
authors: SJ
authors: Acosta-Cota
authors: Departamento de Farmacobiología, Cinvestav-Coapa, Czda. de los Tenorios 235, Col. Granjas Coapa, Deleg. Tlalpan, C.P. 14330 México D.F., Mexico.
authors: Araceli
authors: A
authors: Sánchez-López
authors: Departamento de Farmacobiología, Cinvestav-Coapa, Czda. de los Tenorios 235, Col. Granjas Coapa, Deleg. Tlalpan, C.P. 14330 México D.F., Mexico.
authors: Tzindilu
authors: T
authors: Molina-Muñoz
authors: Departamento de Farmacobiología, Cinvestav-Coapa, Czda. de los Tenorios 235, Col. Granjas Coapa, Deleg. Tlalpan, C.P. 14330 México D.F., Mexico.
authors: Norma L
authors: NL
authors: Gómez-Viquez
authors: Departamento de Farmacobiología, Cinvestav-Coapa, Czda. de los Tenorios 235, Col. Granjas Coapa, Deleg. Tlalpan, C.P. 14330 México D.F., Mexico. Electronic address: dcenturi@cinvestav.mx.
authors: David
authors: D
authors: Centurión
mesh_terms: D018663:Adrenergic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D019540:Area Under Curve; D001381:Azepines / Q000008:administration & dosage / Q000494:pharmacology; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000503:physiopathology*; D003971:Diastole / Q000187:drug effects; D004958:Estradiol / Q000008:administration & dosage* / Q000097:blood / Q000494:pharmacology*; D030762:Estrous Cycle / Q000187:drug effects; D005260:Female; D008729:Methoxamine / Q000008:administration & dosage / Q000494:pharmacology; D009638:Norepinephrine / Q000008:administration & dosage / Q000494:pharmacology; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
chemical_list: D018663:Adrenergic Agents; D001381:Azepines; D001786:Blood Glucose; D014662:Vasoconstrictor Agents; D004958:Estradiol; D013311:Streptozocin; C015603:azepexole; D008729:Methoxamine; D009638:Norepinephrine
keywords: 17β-Oestradiol; Diabetes; Streptozotocin; Sympathetic tone