Uni Z, Platin R, Sklan D
Faculty of Agriculture, Food and Environmental Quality Sciences, Hebrew University of Jerusalem, Rehovot, Israel.
J Comp Physiol B. 1998 May;168(4):241-7. doi: 10.1007/s003600050142.
The location of cell proliferation and differentiation in chicken small intestinal epithelium was examined using immunostaining, measurement of DNA synthesis and brush-border enzyme activities. Chicken enterocytes were removed sequentially from the villus using a modification of the Weiser (1973) method. Alkaline phosphatase activity was relatively constant along the villus tip-crypt axis but decreased in the crypt fractions, whereas sucrase and maltase activities showed higher activity in the upper half of the villus and lower activity in the lower half of the villus and in the crypt. Immunostaining of proliferating cell nuclear antigen indicated the presence of proliferating cells both in the crypt and along the villus, including some activity in the upper portion; the crypt region exhibited a significantly higher number of proliferating cells. Labelled thymidine incorporation into cell fractions after 2 h incubation exhibited a similar pattern of proliferation, with the most active region observed in the crypt and proliferation activity decreasing along the villus. However, some activity was found in the upper half of the villus. After 17 h incubation, cells from the middle region of the villi showed greater proliferation ability than the 2 h incubation. These results indicate that, unlike mammals, chicken enterocyte proliferation is not localized only in the crypt region, and that the site of enterocyte differentiation is not precisely localized.
利用免疫染色、DNA合成测定和刷状缘酶活性检测，对鸡小肠上皮细胞增殖和分化的位置进行了研究。采用改良的韦泽（1973年）方法，从绒毛上依次去除鸡肠上皮细胞。碱性磷酸酶活性沿绒毛顶端-隐窝轴相对恒定，但在隐窝部分降低，而蔗糖酶和麦芽糖酶活性在绒毛上半部分较高，在绒毛下半部分和隐窝中较低。增殖细胞核抗原的免疫染色表明，隐窝和绒毛上都存在增殖细胞，包括上部的一些活性；隐窝区域的增殖细胞数量明显更多。孵育2小时后，标记的胸苷掺入细胞部分呈现出类似的增殖模式，最活跃的区域在隐窝，增殖活性沿绒毛降低。然而，在绒毛上半部分发现了一些活性。孵育17小时后，绒毛中部区域的细胞比孵育2小时时显示出更强的增殖能力。这些结果表明，与哺乳动物不同，鸡肠上皮细胞增殖并非仅局限于隐窝区域，并且肠上皮细胞分化的位置也没有精确地定位。
