Effect of dietary taurine on blood pressure in spontaneously hypertensive rats

Previous studies have shown the dietary supplementation with sulfur amino acids modified the development of hypertension in rats. In the current study, it was found that the addition of taurine (3%) to the drinking water of rats during the period of 4–14 weeks of age had little effect on blood pressure in normotensive Wistar-Kyoto rats (WKR), and slightly retarded the development of hypertension in spontaneously hypertensive rats (SHR). In the stroke-prone substrain (SHR-SP), however, there is a highly significant reduction in the development of hypertension. The endogenous content of taurine in the liver of SHR-SP is less than 50 per cent of that measured in WKR. The livers of the SHR contain an intermediate amount of taurine. The cysteic acid decarboxylase activity of liver is similar in all three strains. The tissues of animals treated chronically with taurine contain only slightly greater amounts of taurine, with small but significant increases in brain taurine being noted. It appears that genetically hypertensive rats, particularly the SHR-SP substrain, have a defect in taurine metabolism, and that this may be related to the severity of hypertension. There is no evidence to suggest that taurine plays a normal regulatory role in blood pressure maintenance.