Fish protein improves blood pressure but alters HDL₂ and HDL₃ composition and tissue lipoprotein lipase activities in spontaneously hypertensive rats

Summary

The two-month effects of dietary fish protein and casein on VLDL, HDL₂ and HDL₃ compositions and hepatic lipase (HTGL) and tissue lipoprotein lipase (LPL) activities were examined in spontaneously hypertensive rats (SHR) at 4 wk of age. After 2 mo of experiment, the fish protein diet induced lower blood pressure (–14 %) as compared to casein. Liver triacylglycerol and total cholesterol concentrations were 1.37- and 1.71-fold lower in the fish protein group than in the casein group, respectively. Total cholesterol concentration in plasma was also diminished by fish protein (–21 %) and was reflected in HDL₂ fraction (–44 %). SHR fed the fish protein diet as compared with those fed casein, showed a significantly low HDL₃ particle number, as measured by diminished HDL₃ mass and apo A-I. The consumption of fish protein did not affect VLDL particle number, but significantly decreased VLDL-triacylglycerol (–32 %) and adipose tissue total lipid concentrations as compared to casein. This was accompanied by diminished HTGL and adipose tissue LPL activities (–10%, –91%, respectively). These data demonstrate that fish protein plays an antihypertensive role and reduces plasma and tissue lipid concentrations. Thus, a fish protein intake might be beneficial for patients with hypertension.