Elevation of Systolic Blood Pressure in Rats Fed Diets Containing Fish and Soybean Proteins ,

Abstract

Significant elevations of systolic blood pressure were observed in weanling rats of a Wistar-derived strain fed a fresh diet of rice, skipjack tuna, soybean products and vegetables (simulated Japanese diet—4% NaCl by weight on a dry basis) for 3 months. No elevations of blood pressure occurred in similar animals fed a control diet or fresh diet from which fish or both fish and soybean products had been omitted. Significant elevation of blood pressure was also observed within 6 weeks in weanling male rats fed a semipurified dry diet (20% casein diet) altered to provide 12% by weight of defatted fish, 2.9% soybean protein and 5.1% casein, salted to provide 4% NaCl. Blood pressures remained normal in pair-fed weanling males fed salted diet (4% NaCl) containing 20% casein or 2.9% soybean protein plus 17.1% casein. It is concluded that fresh or defatted skipjack tuna was responsible for the hypertensive effects of the diets used.