Taurine is known to have antihypertensive and lipid-lowering effects in some experimental models and patients. On the other hand, intracellular free calcium and magnesium play important roles in regulating the tonus of blood vessels and insulin sensitivity. We examined the effect of oral taurine supplementation on blood pressure, serum metabolic parameters, and platelet cytosolic free calcium ([Ca(2+)](i)) and magnesium ([Mg(2+)](i)) concentration in fructose-fed Sprague-Dawley rats. Systolic blood pressure and platelet [Ca(2+)](i) were significantly higher in rats fed a 60% fructose diet. Oral taurine supplementation (1% in drinking water) completely prevented the elevation of blood pressure and an increase in platelet [Ca(2+)](i), but exacerbated hyperinsulinemia, hypertriglyceridemia, and a decrease in platelet [Mg(2+)](i). In conclusion, taurine may ameliorate fructose-induced hypertension in rats by preventing an increase in intracellular free calcium concentration. The blood pressure-lowering effect of taurine appeared to be independent from its effect on glucose and lipid metabolism in this model.