尾吊大鼠胃窦部胃泌素、生长抑素、5－羟色胺和嗜铬颗粒素A免疫反应细胞的变化

AlterationsofGastrin,Somatostatin,SerotoninandChromograninAImmunoreactiveCellsinGastric AntrumofTailSuspendedRats

为深入探讨失重对胃肠内分泌功能的影响，用免疫组织化学ＡＢＣ染色法结合图象分析技术，研究了悬吊模拟失重大鼠胃窦部胃泌素（Ｇａｓ）、生长抑素（ＳＳ）、羟色胺（５－ＨＴ）和嗜铬颗粒素Ａ（ＣｇＡ）免疫反应（－ＩＲ）细胞的密度和灰度变化。结果显示，悬吊大鼠胃窦部Ｇａｓ－ＩＲ细胞和５－ＨＴ－ＩＲ细胞的密度与灰度均较对照鼠增加，而ＳＳ－ＩＲ细胞和ＣｇＡ－ＩＲ细胞的密度与灰度均较对照鼠减低。由于ＳＳ与Ｇａｓ和５－ＨＴ在功能上具有拮抗作用，因而表明，模拟失重状态下，胃窦部内分泌功能稳态可能有变化。

In this study, changes of serotonin(5- HT),gastrin ( Gas)somatostatin(SS)and chro-mogranin A (CgA)immunoreactive cells in the antrum of th e stomach of rat under 90 day tail suspen-sion were observed by using ABC immunostaining techni que combined with image analysis method. Altogether 20 male Wistar rats were used.They were paired and divided into two groups.One groupfor ground- based weightlessness simulation and another for normal control.The rats used for ground- based weightlessness simulation were suspended by the tail in head- down position(一30°)withhind limbs bearing no weight for 90 days.Food and water were supplied freely.The control rats weretreated as same as the experimental rats except suspension. Animals were sacrificed by over dose pen-tobarbital.The gastric antrums were taken out and fixed in Bouin’s solution for l8 hr, then made intoparaffin sections.ABC immunostaining were conducted.The results were analyzed by counting theimmuno-positive cell densities(cell number/mm mucosa )and measuring the positive cell grey levelswith image analyzer.It was found that the 5-HT like immunoreactive(5- HT- IR)cells and Gas-immunoreactive(Gas- IR)cells in th e tail- suspended rats were increased by 41 % and 37%respec-tively(P<0. 0l),their grey levels increased by 33% and 40%respectively(P<0. 01). However,the SS- IR cells and CgA- IR cells decreased by 21%(P<0.05) and 25%(P<0.01)respectively,their grey levels decreased by 28%(P<0. 01) and l2 %(P<0. 05)respectively.The results indicateashift of endocrine balance in the gastric antrum of rats under simulated weightlessness.