Abstract
A diet containing fish meal as a protein source has been found to improve the prognosis of hypertensive diseases in SHRSP, even when given from the hypertensive stage. In the course of studying the mechanism of this preventive effect, we investigated the fluctuation of lipid peroxide (TBARS) and activities of both superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), the enzymes related to removal of lipid peroxides, in the blood of SHRSP fed the fish meal diet from the hypertensive stage. The results obtained were as follows; 1) The serum TBARS level in the control group (stock chow diet) increased with age, and the increase was marked after development of cerebral stroke lesions, whereas the increase in TBARS in the experimental group (fish meal diet) was considerably delayed. Whereas the SOD and GSH-Px activities in erythrocytes in the control group were reduced before the serum TBARS level became elevated, those in the experimental group remained high. 2) In 1% NaCl-loading experiments, elevation of the TBARS level and lowering of SOD and GSH-Px activities in the control group appeared suddenly at an early stage, but in the experimental group these activities remained almost unchanged. From these results, it appears that suppression of cerebrovascular diseases in SHRSP fed a fish meal diet from the hypertensive stage may be due to maintenance of high activities of both SOD and GSH-Px.
