Effects of Oryeongsan improved vascular relaxation in hypertension models

Abstract

Body fluid volumes, which are regulated by the kidneys, are related to blood volume and arterial blood pressure. Oryeongsan (ORS), composition of five herbal medicines, has been widely used to traditional prescription for the treatment of body fluid disorders. The purpose of this study is to investigate the effect of ORS on vascular reactivity and related mechanism in the hypertension model. The experimental models were designed two types of hypertension as follows; 2 kidney 1 clip (2K1C) model and L‐NAME‐induced model. Both 2K1C‐ and L‐NAME‐ induced models were treated with two different dose of ORS (10 and 100 mg/kg/day) for 2 weeks. Blood pressure was markedly increased in both 2K1C and L‐NAME‐induced hypertension models. Interestingly, treatment with ORS significantly improved the impairments of acetylcholine (ACh)‐, sodium nitroprusside (SNP)‐, and atrial natriuretic peptide (ANP)‐induced vascular relaxation of aortic rings in both hypertension models. Treatment with ORS also significantly increased cyclic GMP (cGMP) levels of aortic rings (p<0.01). In addition, both 2K1C and L‐NAME‐induced hypertension models increased ANP, aldosterone levels, and renin activity in plasma, by contrast, treatment with ORS attenuated those levels and activity. These results suggest that ORS ameliorates vascular dysfunction in 2K1C and L‐NAME‐induced hypertension models.