Studies on the biological activity of opines.

它是从海洋无脊椎动物主要是海洋软体动物中分离得到的五种亚氨基酸，如章鱼碱、牛磺平、丙氨酸甲酯、灯盏花素和β-丙氨酸甲酯。它们具有独特的相似结构，都被称为“观点”。阿片类药物是由阿片脱氢酶生物合成的，现在被认为是无脊椎动物厌氧糖酵解的最终产物。阿片脱氢酶存在于几乎所有的软体动物和许多其他无脊椎动物中。因此，鸦片可以通过食物摄入到人体内，但其生物活性尚不清楚。研究了饮食中的鸦片、章鱼碱、牛磺平和丙氨酸对高胆固醇饮食和无胆固醇饮食大鼠血清和肝脏胆固醇水平的影响。在高胆固醇饮食中添加1.5%的章鱼碱可显着降低大鼠血清总胆固醇和极低密度脂蛋白+低密度脂蛋白-胆固醇水平，反之则升高血清高密度脂蛋白-胆固醇水平。在不含胆固醇的饮食中喂食1.5%章鱼碱的大鼠也有同样的趋势。相反，在高胆固醇饮食中添加0.5%的牛磺平显著增加了大鼠血清总胆固醇和极低密度脂蛋白+低密度脂蛋白-胆固醇的水平，降低了血清高密度脂蛋白-胆固醇的水平。在高胆固醇饮食中补充1%丙氨酸对血清总胆固醇水平没有影响。阿片组大鼠盲肠重量也明显高于对照组。服用牛磺平和丙氨酸的大鼠大多表现为腹泻。

It has been isolated five imino acids, such as octopine, tauropine, alanopine, strombine, and beta-alanopine, from marine invertebrates mainly marine molluscs. They have unique similar structure and are all referred to as "opines". Opines, which are biosynthesized by opine dehydrogenases, are now considered to be the end-products of anaerobic glycolysis of invertebrates. Opine dehydrogenases are found in almost all mollusks and many other invertebrates. Opines would be therefore ingested into the human body via foods, but the biological activities of opines are not yet known.The effects of dietary opines, octopine, tauropine and alanopine, on the level of serum and liver cholesterol of rats fed with cholesterol-enriched or cholesterol-free diets were investigated. Dietary supplementation with 1.5% octopine in a cholesterol-enriched diet significantly decreased the serum total-and VLDL+LDL-cholesterol levels and by contrary increased the serum HDL-cholesterol level in rats. The same tendency was observed in the rats fed with 1.5% octopine in a cholecterol-free diet. Contrary, dietary supplementation with 0.5% tauropine in a cholesterol-enriched diet significantly increased the serum total- and VLDL+LDL-cholesterol levels and decreased the serum HDL-cholesterol level in rats. Dietary supplementation with 1% alanopine in a cholesterol-enriched diet did not affect on the serum total cholesterol level. The cecum weight in the rats of opine groups ended also to be heavier than in that of the control rats. Most of rats fed tauropine and alanopine showed diarrhea.