AFP在不同发育时期大鼠胰腺的表达

Expression of AFP during rat pancreatic development

目的:探讨甲胎蛋白(AFP)在大鼠胰腺发育不同阶段的表达情况.方法:采用免疫印迹和免疫组织化学方法检测AFP在不同发育时期大鼠胰腺中的表达.结果:免疫印迹结果显示在不同发育时期大鼠胰腺组织总蛋白中共检测到Mr分别为72000,60000,48000和37000的4种AFP亚型,Mr72000亚型是胚胎15.5d(E15.5)至新生(P0)各时期表达丰度最高者,其次是Mr60000亚型.在E15.5胰腺出现有3种大分子AFP亚型,E18.5胰腺4种亚型的丰度各自达到最高,出生后各有降低或消失,成年胰腺中只有Mr60000亚型的痕量表达.免疫组织化学检测结果显示可分泌蛋白AFP于E18.5至P0特异定位于胰腺间充质细胞.结论:AFP显著高表达于胰腺结构与功能趋于完善的关键发育时期,并特异表达于对胰腺发育具有重要调控作用的胰腺间充质细胞,提示AFP表达与胰腺发育可能具有内在联系.

AIM ：To investigate the dynamic expression profile of alpha-fetoprotein （ AFP ） during pancreatic development. METHODS：The expression and localization pattern of AFP were identified by Western blotting and immunohistochemical staining separately. RESULTS： Four isoforms of AFP （Mr 72 000, 60 000, 48 000 and 37 000） were found by Western blotting in the pancreas tested. The Mr 72 000 AFP expression was the highest from E15.5 to P0, next was the Mr 60 000 AFP. Among all four isoforms of AFP, 3 bigger ones appeared in E15.5. A stronger signal was diaplayed in E18.5, followed by a slight decrease to moderate levels in P0. Only Mr 60 000 isoform was detected in the adult pancreas. Immunolocalisation for AFP revealed that a positive reactivity was detectable at E15.5 pancreas, became stronger in cytoplasm of mesenchyme ceils at E18.5 and declined after birth to a nearly undetectable level in adult. CONCLUSION： AFP is dynamically expressed in developmental rat pancreas and is localized to mesenchyme in perinatal pancreas. The expression of AFP may indicate that AFP might be involved in some aspects of pancreas development.