Antihypertensive property and renal protection by Shichimotsu-koka-to extract in salt-induced hypertension in Dahl strain rats

We determined whether or not the kampo formula, Shichimotsu-koka-to extract, attenuates the development of salt-induced hypertension and provides renal protection against hypertensive injury in Dahl salt-sensitive (Dahl S) rats. A six-week treatment using this formula dose-dependently decreased the systolic blood pressure in Dahl S rats fed a high-salt (2% NaCl) diet. This blood pressure reduction was associated with a decrease in the thickness of the aortic wall. Renal function was not altered with this treatment; however, glomerular sclerotic lesions in the kidney were significantly attenuated. Neither arterial nor tubular lesions were affected. These data suggest that Shichimotsu-koka-to extract exhibits an antihypertensive effect which is associated with partial resolution of glomerular sclerosis in the kidney.