SOLUBLE GUANYLYL CYCLASE ACTIVATOR BAY 41-2272 IMPROVES VASCULAR ACTIVITY OF THORACIC AORTA ISOLATED FROM DOCA HYPERTENSIVE MALE WISTAR RATS (original) (raw)

Hypertensionis the most common cardiovascular disease and of great concern to public health. Bay41-2272 a soluble guanylylcyclase activator induces vasodilation and reduces mortality. DOCA hypertensive group envisaged administration of Deoxycorticosterone acetate salt in soyabean oil in unilaterally nephrectomised male wistarrats @25mg/kg b. wt. subcutaneously twice in a week for 4-weeks with a provision of drinking water containing sodium chloride (1%) ad lib. Sham control unilateral-nephrectomised male wistar rats were treated with soyabean oil providing normal tap water. After completion of four weeks, rats were anaesthetized with pentobarbital sodium to evaluate Mean Arterial Pressure (MAP) and found significant increase (P<0.05)of MAP in DOCA hypertensive rats (160.3±3.02mm of Hg, n=9) compared to sham control(114.6±2.34mm of Hg, n=5). Also in vitro effect of Bay 41-2272 was studied on isolated thoracic aorta. In Bay pre-treated aortic rings of DOCA group, a significant decrease in noradrenaline maximal contraction (Emax0.61±0.03g; n=7) was found as compared to un-incubated aorta (Emax0.99±0.05g; n=5). A significant decrease in acetylcholine relaxation was found in aorta from DOCA hypertensive (Emax=61.19±3.43%, n=7) compared to sham control (Emax=111.10±1.61%; n=6). Bay 41-2272 pre-treatedaorta of DOCA rats, revealed significant increase in acetylcholine relaxation (Emax=97.81±1.68%; n=6) as compared to un-incubated. Result of present study clearly indicates that Bay41-2272 pre-treatment significantly improves the vascular endothelial functions of aorta of DOCA hypertensive rats.