STUDIES ON ALLERGY REGULATING FUNCTION OF HIGHLY UNSATURATED FATTY ACIDS

为阐明食物成分的抗过敏作用，采用培养细胞和实验动物对高不饱和脂肪酸（PUFA）和抗氧化剂的过敏调节活性进行了研究。在细胞水平上，我们发现PUFA增加了IgE的产生，但抑制了其他抗体的产生，并且随着双键数量的增加，它们的IgE产生增强活性变得更强，在亲脂性抗氧化剂的存在下被抑制。另一方面，我们发现PUFA抑制大鼠腹膜渗出细胞（PEC）释放LTB_4，并且随着双键数的增加，活性增强。在此基础上，研究了饲粮脂肪和茶多酚的体内作用，发现富含α -亚麻酸的紫苏油通过降低花生四烯酸在细胞膜磷脂中的比例，降低了大鼠LTB_4的释放活性。相反，TP降低了LTB4的释放活性，但不降低花生四烯酸的含量。此外，我们还研究了二十碳五烯酸（EPA）和二十二碳六烯酸（DHA）在细胞水平上具有很强的过敏调节活性。高EPA鱼油比高DHA鱼油更有效地降低了大鼠PEC中LTB_4的释放活性，但未引起血清IgE水平升高或淋巴细胞产生IgE的增加。这些结果表明，摄入n-3 PUFA和抗氧化剂可减少I型过敏反应，因此这些活性成分的临床应用很重要。

To clarify the anti-allergic effect of food components, allergy regulating activity of highly unsaturated fatty acids (PUFA) and antioxidants was examined using cultured cells and experimental animals. In cellular level, we showed that PUFA enhanced IgE production but inhibited the production of other antibodies, and that their IgE production enhancing activity became stronger with the increase in the number of double bond and was inhibited in the presence of lipophilic antioxidants. On the other hand, we found that PUFA inhibited LTB_4 release from rat peritoneal exudate cells (PEC) and the activity became stronger with the increase in the number of double bond. Then, we examined in vivo effect of dietary fats and tea polyhenol (TP) and found that perrilla oil rich in alpha-linolenic acid decresaed the LTB_4 releasing activity of rats through decrease in the proportion of arachidonic acid in membrane phospholipids. On the contrary, TP decrese LTB4 releasing activity without decreasing the arachidonic acid content. In addition, we studied on dietary effect of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids which exerted strong allergy regulating activity in cellular level. When rats were fed fish oils rich in EPA or DHA at the 10% level, high EPA fish oil decreased LTB_4 releasing activity of rat PEC more efficiently than high DHA oil, while the increase in serum IgE level or enhancement of IgE production by lymphocytes was not induced. These results suggest that intake of n-3 PUFA and antioxidants decrease the type I allergic response and that clinical application of these active components is important thereafter.