Hartmann F, Bissell D M
J Clin Invest. 1982 Jul;70(1):23-9. doi: 10.1172/jci110598.
Formation of heme, bilirubin, and bilirubin conjugates has been examined in mucosal cells isolated from the rat upper small intestine. Intact, viable cells were prepared by enzymatic dissociation using a combined vascular and luminal perfusion and incubated with an isotopically labeled precursor, delta-amino-[2,3-3H]levulinic acid. Labeled heme and bile pigment were formed with kinetics similar to those exhibited by hepatocytes. Moreover, the newly formed bilirubin was converted rapidly to both mono- and diglucuronide conjugates. In addition, cell-free extracts of small intestinal mucosa from rats or humans exhibited a bilirubin-UDP-glucuronyl transferase activity that was qualitatively similar to that present in liver. The data suggest that the small intestinal mucosa normally contributes to bilirubin metabolism.
已对从大鼠上段小肠分离出的黏膜细胞中血红素、胆红素及胆红素结合物的形成进行了研究。通过联合血管和管腔灌注的酶解方法制备完整、有活力的细胞，并与同位素标记的前体δ-氨基-[2,3-³H]乙酰丙酸一起孵育。形成的标记血红素和胆色素的动力学与肝细胞表现出的相似。此外，新形成的胆红素迅速转化为单葡萄糖醛酸和双葡萄糖醛酸结合物。另外，大鼠或人类小肠黏膜的无细胞提取物表现出的胆红素-UDP-葡萄糖醛酸基转移酶活性在性质上与肝脏中的相似。这些数据表明小肠黏膜通常参与胆红素代谢。
