tert-Butyl hydroperoxide-mediated vascular responses in DOCA-salt hypertensive rats
| Autor: | Sunday O. Awe, Stanley E. D'Souza, Ayotunde S.O Adeagbo, Nina L. Tsakadze |
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| Rok vydání: | 2003 |
| Předmět: |
Male
medicine.medical_specialty Antioxidant Free Radicals Physiology medicine.medical_treatment Blood Pressure Cyclic N-Oxides Rats Sprague-Dawley Superoxide dismutase chemistry.chemical_compound tert-Butylhydroperoxide Internal medicine medicine Animals Desoxycorticosterone Pharmacology Dose-Response Relationship Drug biology Superoxide Dismutase urogenital system Chemistry Anatomy Free radical scavenger Rats Endocrinology medicine.anatomical_structure Vasoconstriction Catalase Hypertension Circulatory system biology.protein tert-Butyl hydroperoxide Molecular Medicine Spin Labels medicine.symptom circulatory and respiratory physiology Blood vessel |
| Zdroj: | Vascular Pharmacology. 40:51-57 |
| ISSN: | 1537-1891 |
| Popis: | tert-Butyl hydroperoxide (t-BOOH), a membrane permeant oxidant, elicits enhanced vasoconstriction of perfused kidney and mesenteric arterial beds isolated from DOCA-salt-induced hypertensive rats. We hypothesize that enhanced vasoconstriction to t-BOOH during DOCA-salt hypertension involves free radical species and decreases in the expression of the endogenous antioxidant enzyme, superoxide dismutase (SOD). t-BOOH (0.01-50 micromol) dose-dependently constricted the perfused kidney and mesenteric vascular beds (MVB) of rats. Infusion of tempol (100 microM), a free radical scavenger, reduced the constrictor responses from 116.70+/-16.65% to 57.45+/-9.25% (kidneys) and from 72.91+/-3.70% to 48.10+/-0.10% (mesenteric beds). t-BOOH-induced vasoconstriction of both vascular beds were also significantly reduced in DOCA-salt rats treated chronically (15 mg/kg ip, 3 weeks) with tempol (DOCA/TEMPOL). Catalase (500 IU) did not attenuate t-BOOH-induced responses in vascular beds of DOCA/TEMPOL rats. Western blot analyses showed significant reduction in Cu/Zn-SOD expression in DOCA-salt versus sham rats of both vascular preparations; SOD expressions were protected from down-regulation in DOCA/TEMPOL vascular beds. This study suggests that free radical species is involved in both t-BOOH-induced constrictions and in the down-regulation of SOD protein expressions during DOCA-salt hypertension. |
| Databáze: | OpenAIRE |
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