The relationship between the hypocholesterolemic sction of Shiitake and phospholipid metabolim

本研究旨在探讨香菇降血脂作用与大鼠血脂代谢的关系。结果表明：(1)在降低血浆胆固醇浓度的同时，饲粮中添加酸垂腺嘌呤可显著降低肝脏微粒体PC/PE和delta6 -去饱和酶活性，且呈剂量依赖性和时间依赖性。血浆胆固醇浓度与PC/PE、delta6 -去饱和酶活性、花生四烯酸/亚油酸比值呈正相关。血浆PC亚油酸的升高体现在16:0 - 18:2分子种比例的升高。(2)血浆PC/PE比、delta6 -去饱和酶活性和血浆PC分子种类（16:0 - 18:2）的变化率均快于血浆胆固醇浓度的变化率。(3)饲粮中垂垂腺嘌呤对胆固醇、脂肪酸、磷脂等脂质代谢的影响与饲粮脂肪类型无关。由此可见，饲粮中的垂垂腺嘌呤通过改变肝脏磷脂类组成和血浆脂蛋白磷脂分子种类组成来降低血浆胆固醇浓度。

This study was conducted to investigate the relationship between the plasma cholesterol-lowering effect of Shiitake (Lentinus edodes) mushroom and the phospholipid metabolism in rats. The summary of the results obtained were as follows :(1) The liver microsomal PC/PE ratio and DELTA6-desaturase sctivity were significantly decreased by dietary supplementation with eritadenine, a hypocholesterolemic factor of the L.edodes mushroom, in a dose dependent and time-dependent manner in addition to the decrease in the plasma cholesterol concentration. There was a significant correlation between the plasma cholesterol concentration and the PC/PE ratio and DELTA6-desaturase activity, arachidonioc/linoleic acid ratio. The increase in the linoleic acid of plasma PC was reflected in the increase in the proportion of 16 : 0-18 : 2 molecular species.(2) The rate of changes in the PC/PE ratio, DELTA6-desaturase sctivity and 16 : 0-18 : 2 molecular species of plasma PC was faster than that of plasma cholesterol concentration.(3) The effect of dietary eritadenine on on the metabolism of lipida, such as cholesterol, fatty acids and phospholipids, was independent of dietary fat types.From these results, it was suggested that dietary eritadenine decreases the plasma cholesterol concentration through alterations of hepatic phospholipid class composition and molecular species composition of plasma lipoprotein phospholipids.