Pathophysiology and clinical meaning of physiologic cholestasis

我们研究了许多正常婴儿的胆汁淤积。新生儿胆汁淤积多见于婴儿期，出生后4周达高峰，婴儿维生素K缺乏症、母乳性黄疸、新生儿肝炎综合征等疾病主要以肠道胆汁酸分泌不足为主。这些疾病多见于母乳喂养的婴儿，因此我们研究了母乳对原代培养的新生大鼠肝细胞肝功能，特别是DNA合成的影响。分离的新生大鼠肝细胞在含人乳的培养液中培养，或在对照组中培养。肝细胞DNA合成通过掺入胸腺苷的方法进行测定。母乳对新生大鼠肝细胞DNA合成的促进作用明显高于对照组。母乳的生位活性与人表皮生长因子(HEGF)浓度无相关性。抗HEGF抗体不能完全抑制该细胞的生位活性。这些结果提示人乳中存在HEGF以外的谷氨酸，从而阐明了生理性胆汁淤积的临床过程。然而，仍然有一些问题，特别是胆汁淤积和母乳喂养之间的联系，仍然有待解决。

We studied the cholestasis which physiologically seen in many normal infants. The cholestasis was ordinarily seen in neonatal through infantile period, , and that reached the top level at late neonatal period of 4 weeks after birth.We found that the diseases of infantile vitamin K deficiency, breast milk jaundice and neonatal hepatitis syndrome were occured mainly based on insufficiency of bile acid secretion into the intestine. These diseases were usually seen in breast-fed infants, so that we studied the effect of human milk on liver function, especially DNA synthesis in primary cultured neonatal rat he atocytes. Isolated hepatocytes in 5-oay old neonatal rats were cultured in a medium with human milk, or with controls. DNA syntheses of hepatocytes were measured by incorporation on P H)thysidine. Human milk promoted DNA synthesis in neonatal rat hepatocytes more than that of controls. The sitogenic activity of human milk shoved no correlation with the concentration of, human epidernal growth factor(HEGF). Anti-HEGF antibody did not inhibit the sitogenic activity completely. These results suggest the presense of sitogens other than HEGF in human milk.From, our results, clinical course of physiologic cholestasis was elucidated. Hovever some problems, espegi 11 the association between the cholestasis and breast feeding, remains to be solved.