S6 Document heading Antihypertensive effect of rhizome part of Acorus calamus on renal artery occlusion induced hypertension in rats Pinal Patel 1 , Jitendra Vaghasiya 1* , Ashokji Thakor 1 , Jitesh Jariwala 2 1 Department of Pharmacology, Babaria Institute of Pharmacy, BITs edu campus, Gujarat Technological University, Gujarat, India. 2 Department of Pharmacognosy, Babaria Institute of Pharmacy, BITs edu campus, Gujarat Technological University, Gujarat, India. Asian Pacific Journal of Tropical Disease (2012)S6-S10 Asian Pacific Journal of Tropical Disease journal homepage:www.elsevier.com/locate/apjtd *Corresponding author: Dr. Jitendra Vaghasiya Department of Pharmacology, Babaria Institute of Pharmacy, BITs edu campus, Gujarat Technological University Gujarat, India. Tel: +919825244874 E-mail: j_vaghasiya@yahoo.com 1. Introduction Renovascular hypertension is a common secondary hypertension and the most prevalent form of curable hypertension. Although presently used antihypertensive agents have been shown to reduce the incidence of cardiovascular events, but to control elevated blood pressure (BP) continues to be a worldwide public health problem. Hence, newer antihypertensive agents are needed to expand therapeutic options, increase treatment efficacy, decrease side effects, and enhance patient adherence. Renovascular hypertension occurs in humans due to renal artery constriction, usually from atherosclerotic or fibromuscular dysplastic renal disease, since this lowering of renal perfusion pressure causes the kidney to over produce renin, leads to a continual activation of the renin angiotensin-aldosterone system [1,2] . The renin-angiotensin-aldosteron system (RAAS) plays an important role in the control of cardiovascular homeostasis, affecting both blood pressure and fluid volume and is one of the most important ethiological candidates in hypertension. Originally, the RAS was known solely as an endocrine system, in which angiotensinogen of hepatic origin is secreted into the systemic circulation and cleaved by renin and angiotensin- converting enzyme (ACE), to produce the active peptide angiotensin II (AngII). It is now well documented that RAS, including all the components of the enzymatic pathway, may reside within several individual organs or tissues such as kidney, lung, heart and vascular smooth muscle cells, where it is believed to act in a functionally independent paracrine/ autocrine fashion [3] . There is a clear link between oxidative stress and the development of angiotensin II - induced hypertension [4,5] but the exact mechanisms are not yet fully understood. More than a decade ago, it was concluded from indirect evidence that angiotensin II may induce reactive oxygen ARTICLE INFO ABSTRACT Article history: Received 15 June 2012 Received in revised form 27 June 2012 Accepted 18 October 2012 Available online 28 October 2012 Keywords: acorus calamus hypertension nitric oxide plasma renin activity Objective: The rhizomes part of Acorus calamus (AC) having the calcium inhibitory effect and diuretic activity which may potentiate Na+ excretion in hypertension induced by occlusion of renal artery. Therefore this study was aimed to investigate the effect of AC on experimentally induced hypertension. Methods: Hypertension in rats was induced by clamping the left renal artery for 4h by arterial clamp (2K1C). At the end of experiment animal were anesthetized with ketamine (50 mg/kg). Carotid artery was cannulated which was connected to pressure transducer for estimation of blood pressure. Results: Ethyl acetate extract of Acorus calamus rhizomes (EAAC) treated rats that underwent hypertension, demonstrated significant (P < 0.01) lower systolic blood pressure and diastolic blood pressure when compared with 2K1C rats indicated blood pressure lowering activity. Plasma renin activity was significantly (P < 0.05) decreased in EAAC treated rats compared to 2K1C rats. EAAC treated rats that underwent hypertension demonstrated significant (P < 0.01) lower mean blood urea nitrogen and creatinine when compared with 2K1C rats. Lipid peroxidation was significantly (P < 0.001) decreased, where as nitric oxide level in tissue was significantly elevated in EAAC treated rats. Antioxidant enzymes like glutathione, superoxide dismutase and catalase were significantly (P < 0.05, P < 0.01, P < 0.001) increased in EAAC treated rats when compared to 2K1C rats. Conclusions: In conclusions, EAAC treatment attenuated renal artery occlusion induced hypertension via nitric oxide generation and decreases the plasma renin activity. Contents lists available at ScienceDirect