Abstract

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

ShahidPrawez*, Azad A Ahanger, Kathirvel Kandasamy, Thakur U Singh,Santosh K Mishra and Souvendra N Sarkar

Abstract

Hypertensionis the most common cardiovascular disease and of greatconcern to public health. Bay41-2272 a soluble guanylylcyclaseactivator induces vasodilation and reduces mortality. DOCAhypertensive group envisaged administration of Deoxycorticosteroneacetate salt in soyabean oil in unilaterally nephrectomised malewistarrats @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 ratswere treated with soyabean oil providing normal tap water. Aftercompletion of four weeks, rats were anaesthetized with pentobarbitalsodium to evaluate Mean Arterial Pressure (MAP) and foundsignificant increase (P<0.05)of MAP in DOCA hypertensive rats(160.3±3.02mm of Hg, n=9) compared to sham control(114.6±2.34mmof Hg, n=5). Also in vitro effect of Bay 41-2272 was studied on isolated thoracic aorta. InBay pre-treated aortic rings of DOCA group, a significant decrease in noradrenaline maximalcontraction (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 aortafrom 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 significantincrease 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.

Keywords: DOCA-salt, Hypertension,Mean Arterial Pressure, Bay 41-2272,vascular activity, thoracic aorta, male, wistar rats.