阿片样肽在人胎儿胸腺组织的表达

Expression of opioid peptides in human fetal thymus

目的：探讨阿片样肽在人胎儿胸腺组织及其上皮细胞的表达。方法：用放射免疫测定药盒测定人胎儿胸腺组织匀浆提取物中β内啡肽（β Ｅ Ｐ） 和亮氨酸脑啡肽（ Ｌ Ｅ Ｎ Ｋ） ，同时用免疫组化方法检测胎儿胸腺组织冷冻切片和石蜡切片中的β Ｅ Ｐ 和 Ｌ Ｅ Ｎ Ｋ 的表达。结果：人胎儿胸腺组织提取液中β Ｅ Ｐ（１２ 例） 和 Ｌ Ｅ Ｎ Ｋ（１１ 例） 的含量（ｐｇ／１００ ｍｇ 湿重组织） 分别为５５０ ．８９±１９５ ．１１ 和１ ０２８ ．４４ ±６３２ ．７８ 。比较胎龄＜ ２０ 周组和≥２０ 周组的胸腺组织提取液中两种阿片样肽的含量差异均无显著性（ Ｐ＞ ０ ．０５） 。免疫组化检测发现，胸腺组织中β Ｅ Ｐ 和 Ｌ Ｅ Ｎ Ｋ 阳性反应细胞的分布部位与角蛋白阳性反应细胞相一致，表明胸腺上皮细胞可表达这两种阿片样肽。结论：本研究结果表明，人胎儿胸腺组织在胎龄１６ ～２０ 周时即可表达β Ｅ Ｐ 和 Ｌ Ｅ Ｎ Ｋ，胸腺上皮细胞与产生这两种阿片样肽有关。

Objective:To investigate expression of opioid peptides in human fetal thymus.Methods:By using radio immunoassay the concentrations of β endorphin(β EP) and leucine enkephalin(L ENK) were evaluated in extracts of human fetal thymus and immunohistochemistry technique was used to detect the expression of two opioid peptides in fetal thymus sections.Results:The concentrations (pg/100 mg wet tissue) of β EP(n=12) and L ENK(n=11) in extracts of fetal human thymus were 550.89±195.11 and 1 028.44±632.78 respectively. In both concentrations of β EP and L ENK in thymus extracts there were no significant differences between groups of <20 week and ≥20 week fetus. Immunohistochemistry employed in fetal thymus sections revealed that most cells that were monoclonal antibodies positively reactive against to β EP and L ENK were consistent in location with the cells that reacted to keratin monoclonal antibody.Conclusions:This study demonstrated that opioid peptides β EP and L ENK in human fetal thymus expressed as earlier as in 16 to 20 week fetuses. The resources of two opioid peptides generated in fetal thymus were related to thymic epithelial cells.