Nitric oxide inhibits calcium release from sarcoplasmic reticulum of porcine tracheal smooth muscle cells
Nitric oxide inhibits calcium release from sarcoplasmic reticulum of porcine tracheal smooth muscle cells
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DOI：
10.1152/ajplung.1997.272.1.l1
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发表时间：
1997-01-01
影响因子：
4.9
通讯作者：
Sieck, GC
中科院分区：
文献类型：
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作者：
Kannan, MS;Prakash, YS;Sieck, GC
在本研究中，一氧化氮供体，S-亚硝基-N-乙酰青霉胺（SNAP），对肌浆网（SR）的Ca 2+释放新鲜分离的猪气管平滑肌（TSM）细胞的影响进行了研究。使用视频荧光显微镜对负载Fura 2的TSM细胞进行成像。乙酰胆碱（ACh）和咖啡因分别通过1，4，5-三磷酸肌醇（IP 3）受体和Ryanodine受体（RyR）诱导SR Ca ~（2+）释放。SNAP抑制乙酰胆碱诱导的SR Ca 2+释放在0和2.5 mM的细胞外Ca 2+。降解SNAP对ACh诱导的SR Ca ~（2+）释放无影响。SNAP还抑制咖啡因诱导的SR Ca 2+释放。ACh诱导的Ca ~（2+）内流不受SNAP的影响，当SR再负荷被thapsigargin阻断时。SNAP也不影响SR Ca 2+再摄取。鸟苷3 '，5'-环一磷酸（cGMP）的膜渗透类似物8-溴-cGMP模拟了SNAP的作用。这些结果表明，在猪TSM细胞中，SNAP通过抑制SR Ca 2+释放通过IP 3和RyR，但不是通过抑制流入或补充SR Ca 2+商店，减少细胞内Ca 2+对ACh和咖啡因的反应。这些作用可能通过cGMP依赖性机制介导。
In the present study, effects of the nitric oxide donor, S-nitroso-N-acetylpenicillamine (SNAP), on sarcoplasmic reticulum (SR) Ca2+ release were examined in freshly dissociated porcine tracheal smooth muscle (TSM) cells. Fura 2-loaded TSM cells were imaged using video fluorescence microscopy. SR Ca2+ release was induced by acetylcholine (ACh), which acts principally through inositol 1,4,5-trisphosphate (IP3) receptors, and by caffeine, which acts principally through ryanodine receptors (RyR). SNAP inhibited ACh-induced SR Ca2+ release at both 0 and 2.5 mM extracellular Ca2+. Degraded SNAP had no effect on ACh-induced SR Ca2+ release. SNAP also inhibited caffeine-induced SR Ca2+ release. ACh-induced Ca2+ influx was not affected by SNAP when SR reloading was blocked by thapsigargin. SNAP also did not affect SR Ca2+ reuptake. The membrane-permeant analogue of guanosine 3',5'-cyclic monophosphate (cGMP), 8-bromo-cGMP, mimicked the effects of SNAP. These results suggest that, in porcine TSM cells, SNAP reduces the intracellular Ca2+ response to ACh and caffeine by inhibiting SR Ca2+ release through both IP3 and RyR, but not by inhibiting influx or repletion of the SR Ca2+ stores. These effects are likely mediated via cGMP-dependent mechanisms.