摘要
目的研究肿瘤坏死因子α(TNF-α)对肾小球系膜细胞(GMCs)胞内钙离子浓度([Ca2+]i)及细胞收缩的影响,证明TNF-α通过1,4,5-三磷酸肌醇受体(IP3Rs)增强GMCs对缩血管物质的易感性是肝肾综合征的重要机制。方法应用大鼠GMCs株,测量时均选无钙缓冲液及内皮素(ET)刺激。分正常对照ET刺激组(0h组)、TNF-α处理4hET刺激组(4h组)、TNF-α处理24hET刺激组(24h组);另设上述3组于ET前10min加入IP3Rs阻断剂2-氨基乙氧基联苯硼酸盐(2-APB)。应用Fluo-3/AM标记及激光共聚焦显微镜,观察TNF-α预处理后GMCs对ET刺激后[ca2+]i的变化及2-APB阻断后的变化。同时测量各组GMCs收缩前后表面积的变化以明确收缩幅度。结果ET刺激可使GMCs在短时间内[Ca22+]i迅速、显著增加,TNF-α4h、24h组[Ca2+]i上升幅度尤为明显[4h:(648.08±267.11)nmol/L;24h:(879.30±260.29)nmol/L;0h:(619.93±258.94)nmol/L,F:5.486,4hvs0h:P〈0.05;24hvs0h:P〈0.05;24hvs4h:P〉0.05]。2-APB阻断后3组细胞对ET刺激均失去反应,[Ca2+]i无上升。ET刺激可使各组细胞面积缩小;TNF-α 4h、24h组上述效应更加明显[4h:(2198±340)μm2;24h:(2260±553)μm2;0h:(2436±474)μm2,F=4.001,4hvs0h:P〈0.05;24hvs0h:P〈0.05;24hvs4h:P〉0.05)。结论TNF-α可增加ET刺激引起的[Ca2+]i上升进而引起细胞收缩,并证明是通过IP3Rs通路产生效应的,这可能是肝肾综合征时肾脏对缩血管物质产生高敏性进而引起。肾小球滤过率下降的重要机制。
Objective To investigate the effect of tumor necrosis factor-α (TNF-α) on intracellular calcium concentration ( [ Ca2 +] i ) and the contraction of glomerular mesangial cells ( GMCs), and prove that hypercontractility of GMCs induced by TNF-α in hepatorenal syndrome(HRS) was connected with inositol 1,4,5-trisphophate receptors (IP3Rs). Methods GMCs were divided into TNF-α-treated 0 h, 4 h, and 24 h groups. Another 3 groups were blocked by 2-APB. The effect of TNF-αon [ Ca2 + ] i was identified and observed whether it could be blocked by 2-APB. Contraction of GMCs was determined by accessing the surface area of cells before and after contraction. Results TNF-α significantly increased ET-induced calcium release, in that we found higher [ Ca2 + ] i after stimulated by ET in TNF-α -treated 4 h group and 24 h group[ 4 h: (648.08 ± 267.11 )nmol/L; 24 h: (879. 30 ±260. 29) nmol/L; 0 h: (619. 93 ± 258. 94) nmol/L,F =5.486,4hvs0h:P 〈0.05;24hvs0h:P 〈0.05;24hvs4h:P 〉0.05]. This phenomenon can be totally blocked by 2-APB in all groups. The change in planar surface area in response to ET was slightly in control cells but significantly enhanced in TNF-α -treated cells [ 4 h:(2198 ± 340)μm2; 24 h: (2260 ~553) μm2 ; 0 h: (2436 ±474) μm2, F =4. 001,4 h vs 0 h: P 〈0. 05 ; 24 h vs 0 h: P 〈0. 05 ;24 h vs 4 h : P 〉 0. 05 ]. Conclusion TNF-α can enhance ET-induced sarcoptasmic reticulum Ca2 + re-lease and increase the contractile responses of GMCs to ET, which is associated with IP3Rs. TNF-α is re-sponsible for hyperconstractility of glomeruli in HRS.
出处
《中国医师杂志》
CAS
2013年第1期11-14,共4页
Journal of Chinese Physician
基金
国家自然科学基金(N030270607)
关键词
肿瘤坏死因子Α
钙
代谢
肾小球膜
细胞学
肝肾综合征
Tumor necrosis factor-alpha
Calcium/metabolism
Glomerular mesangium/cytology
Hepatorenal syndrome