Physiological and Biochemical Study of Gastrointestinal Functions.

(1)饲喂乳清酸饲粮时，饲喂酪蛋白饲粮的大鼠肝脏脂质水平显著高于饲喂鸡蛋蛋白或大豆蛋白的大鼠。在含有酪蛋白的日粮中添加山羊角酸可降低肝脏超氧化物歧化酶活性，增加血清鸟氨酸氨基甲酰转移酶活性，增加肝脏1,2-二酰基甘油浓度。给药后的肝损伤可能是由于1,2-二甘油浓度的增加和肝超氧化物歧化酶活性的降低。(2)从红辣椒中发现了乙酰辅酶a羧化酶抑制剂9-Oxooctadeca 10,12-二烯酸。其活性是正常脂肪酸的50倍。(3)饲粮中甜菜纤维有抑制1,2-二甲基肼诱导的异常隐窝灶形成的作用。此外，我们还发现抗亚洲蓟GMI能抑制紫外线照射诱导的异常隐窝病灶的形成，而甜菜纤维的添加则不能。(4) 1,2-二甲基肼诱导结肠上皮细胞凋亡及p53水平升高。进一步观察结肠活化素mRNA水平升高。这是首次发现激活素是阻止细胞凋亡周期的因子。

(1) When rats were fed an orotic acid diet, liver lipid level of rats fed a diet containing casein was significantly higher than that of a diet containing egg protein or soybean protein. The addition of an orotic acid to a diet containing casein caused to decrease liver superoxide dismutase activity, to increase serum ornithine carbamoyl transferase activity, to increase the hepatic concentration of 1,2-diacylglycerol. Liver damage by administration of an orotic acid might be due to the increased concentration of 1,2-diaclglycerol and decreased activity of hepatic superoxide dismutase.(2) 9-Oxooctadeca 10,12-dienoic acid as acetyl CoA carboxylase inhibitor from red pepper was found. Its activity was 50 fold higher as compared with the normal fatty acids.(3) Dietary beet fiber had a role to supprees the formation of the aberrant crypt foci induced by 1,2-dimethylhydrazine. Furthermore, it was found that the formation of the aberrant crypt foci induced by nu -ray irradiation was suppressed by the injection of anti-asialo GMI, but not by the addition of beet fiber.(4) Apoptosis and p53 level in epithelial cell of colon was induced by the administration of 1,2-dimethylhydrazine. Further observation was increased level of activin mRNA in colon. This is the first finding that activin is a factor to stop the cell cycle in apoptosis.