松果体及其褪黑素对大鼠胸腺细胞凋亡的影响  

EFFECT OF PINEAL GLAND AND MELATONIN ON APOPTOSIS OF THYMOCYTES IN RATS

作　　者：周瑞祥[1,2] 刘卉[1,2] 黄云梅[1,2] 魏建恩[1,2] 谢美容[1,2] 林静[1,2] 林建银[3] 

机构地区：[1]福建医科大学人体解剖与组织胚胎学系 [2]神经生物学研究中心,福州350004 [3]福建医科大学人体解剖与组织胚胎学系分子医学研究中心,福州350004

出　　处：《中国组织化学与细胞化学杂志》2006年第3期333-337,共5页Chinese Journal of Histochemistry and Cytochemistry

基　　金：福建省自然科学基金(C0410028);福建省教育厅项目(2005K043)

摘　　要：目的探讨松果体及其褪黑素对胸腺细胞凋亡的影响以及Caspase-3的表达。方法选用清洁级SD大鼠,分为正常对照组、假手术对照组、松果体摘除组、松果体摘除+褪黑素腹腔注射7.5mg/kg/d组和松果体摘除+褪黑素腹腔注射15mg/kg/d组。术后4、8周取材。运用TUNEL法检测胸腺细胞的凋亡程度,用ABC法染胸腺Caspase-3阳性细胞,计算机图像分析仪测量阳性细胞面积及其染色强度。以RT-PCR法检测褪黑素干预原代培养胸腺细胞Caspase-3的表达。结果松果体摘除后8周时胸腺细胞凋亡显著增加,补充褪黑素则能明显减少胸腺细胞的凋亡。Caspase-3阳性细胞主要见于胸腺皮质,松果体摘除后胸腺皮质Caspase-3阳性细胞面积增加明显,补充褪黑素则使其下降。褪黑素能上调培养胸腺细胞Caspase-3的表达水平。结论松果体能调控大鼠胸腺细胞的凋亡,松果体摘除促进胸腺细胞的凋亡,补充褪黑素能缓解相关影响。Objective To investigate the effect of pinealectomy and melatonin on the apoptosis and caspase-3 expression of thymocytes. Methods SD rats were divided into 5 groups： normal controls, shamoperated controls, pinealectomy, pinealectomy ＋ MLT injection 7.5mg/kg/d, and pinealectomy ＋ MLT injection 15mg/kg/d. The animals were sacrificed at 4 or 8 weeks after operation. The apoptosis of thymocytes was detected by TUNEL method. Caspase-3 positive cells in the thymus were dyed with immunocytochemical ABC methods and measured by computer image analysis. The Caspase-3 expression of cultured thymocytes was tested by RT-PCR method. Results The apoptosis of thymocytes was on the rise after pinealectomy, which was down-regulated by exogenous melatonin. The area of Caspase-3 positive cells in the cortex rose significantly, which was reduced by melatonin. Melatonin enhanced the expression of Caspase- 3 in thymocytes. Conclusion The pineal gland can regulate the apoptosis of thymocytes. Pinealectomy enhances the apoptosis of thymocytes. Rejuvenation of degenerative thymus can be achieved by melatonin administration.

关 键 词：松果体 胸腺细胞 凋亡 CASPASE-3 大鼠 

分 类 号：R392.6[医药卫生—免疫学]