BAY 41-2272 Treatment Improves Acetylcholine-Induced Aortic Relaxation in L-NAME Hypertensive Rats

Hypertension, an emerging problem of recent era, and many pathophysiological factors are participating to produce the disease. Nitric oxide (NO) is an important constituent to ameliorate hypertensive condition. Inhibition of endogenous NO synthase by L-N^G-Nitroarginine methyl ester (L-NAME) was responsible for generating hypertension in rats. BAY 41-2272 (5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridine-3-yl]-pyrimidin-4-ylamine), a soluble guanylyl cyclase activator, restricts rise of blood pressure and shows cardioprotective activity. The aim of the present study was to analyze effect of short-term BAY 41-2272 treatment on blood pressure and vascular function. Male Wistar rats were randomly divided into three groups such as control (group-A), hypertensive (group-B), and BAY 41-2272-treated hypertensive (group-C) rats. Normal saline was administered intramuscularly to control rats for last 3 days (days 40, 41, and 42) of total 42 days treatment, whereas rats of group-B and group-C were treated with L-NAME hydrochloride in drinking water at 50 mg/kg body weight daily for 42 days. Also, normal saline and BAY 41-2272 were administered for last 3 days at two different dosages at 1 and 3 mg/kg body weight/day intramuscularly to group-B and group-C rats, respectively. Administration of BAY 41-2272 for 3 days was not sufficient enough to decrease mean arterial pressure of hypertensive rats significantly. BAY at both the treatment dosages significantly ameliorate acetylcholine-induced maximal aortic relaxation compared with BAY-untreated hypertensive rats. Findings of the present study indicate that even shorter period of BAY 41-2272 treatment (3 days) improves vascular relaxation.