慢性低氧大鼠 TRPC1表达与肺动脉收缩变化时间曲线关系

摘要

目的：探讨慢性低氧（chronic hypoxia，CH）上调 TR-PC1表达和 SOCE 介导肺动脉（pulmonary arteris，PAs）收缩的时间曲线。方法清洁级♂ SD 大鼠，常压低氧（氧分压为9.5％～10.5％）饲养，观察在不同时间点 CH 对 TRPC1表达量和 SOCE 介导的 PAs 收缩的影响，描记其时间依赖性曲线。结果① CH 上调平均右心室收缩压（mRVSP），低氧1 d 压力增高明显，7 d 达到最大值，21 d 后达到稳定；右心室质量指数（RVMI）低氧3 d 后开始增高，此后一直呈持续增高状态，直到21 d 达到稳定；②半定量 RT-PCR 检测显示， CH 上调 TRPC1 mRNA 的表达量，低氧1 d 上调明显，3 d 达到最大值一直维持到7 d，21 d 后达到稳定；③ CH 上调SOCE 介导的 PAs 收缩，低氧3 d 开始上调，7 d 达到最大值，21 d 后达到稳定。结论CH 早期 TRPC1／SOCE 明显上调，两者的时间曲线具有相关性，表明 TRPC1和 SOCE 的上调在慢性低氧致肺高压的机制中发挥着重要作用。%Aim To evaluate the time-course curve of expression of TRPC1 and vascular tone of pulmonary arteries(PAs)mediated by SOCE in chronic hypoxia pulmonary hyperte-nsion rats.Methods Both tension of PA rings and expression of TRPC1 were tested in CH exposure (1 0.0 % ±0.5 %partialpressure ofoxygen ) induced pulmonary hypertensive (PH)rats,and the time-course curve(detected respectively in CH 1 ,3,5, 7,1 4,21 d)was traced.Results ①CH could up-regulate the mean right ventricular pressure(mRVSP) ,which was increased significantly on 1 d,and reached the maximum on 7d;right ventricular weight index (RV-MI)began increase on 3d,and kept rising;②semi-quantitative reverse transcription polyme-rase chain reaction (RT-PCR)was performed to detect the expression of TRPC1 in PAs.The expression of TRPC1 increased significantly on 1 d,and reached the maxi-mum on 3d;③CH could up-regulate the vascular tone of PAs mediated by SOCE,which was increased signif-icantly on 3d,and reached the maximum on 7d.Con-clusions TRPC1 /SOCE increases significantly in the early days of CH,and the time-course curve of the two has correlation,which reflects the important role of the upregulation of TRPC1 /SOCE in the process of chronic hypoxia pulmonary hypertension.