Durante W, Kroll M H, Christodoulides N, Peyton K J, Schafer A I
Houston VA Medical Center, TX 77030, USA.
Circ Res. 1997 Apr;80(4):557-64. doi: 10.1161/01.res.80.4.557.
Since recent studies demonstrate that vascular smooth muscle cells synthesize two distinct guanylate cyclase-stimulatory gases, NO and CO, we examined possible regulatory interactions between these two signaling molecules. Treatment of rat aortic smooth muscle cells with the NO donors, sodium nitroprusside, S-nitroso-N-acetyl-penicillamine, or 3-morpholinosydnonimine, increased heme oxygenase-I (HO-1) mRNA and protein levels in a concentration and time-dependent manner. Both actinomycin D and cycloheximide blocked NO-stimulated HO-1 mRNA and protein expression. Nuclear run-on experiments demonstrated that NO donors increased HO-1 gene transcription between 3- and 6-fold. In contrast, NO donors had no effect on the stability of HO-1 mRNA. Incubation of vascular smooth muscle cells with the membrane-permeable cGMP analogues, dibutyryl cGMP and 8-bromo-cGMP, failed to induce HO-1 gene expression. Treatment of vascular smooth muscle cells with NO donors also stimulated the production and release of CO, as demonstrated by the CO-dependent increase in intracellular cGMP levels in coincubated platelets. Finally, incubating vascular smooth muscle cells with interleukin-1 beta and tumor necrosis factor-alpha induced NO synthesis and also significantly increased the level of HO-1 protein. The cytokine-stimulated production of both NO and HO-1 protein in smooth muscle cells was blocked by the NO synthase inhibitor methyl-L-arginine. These results demonstrate that exogenously administered or endogenously released NO stimulates HO-1 gene expression and CO production in vascular smooth muscle cells. The ability of NO to induce HO-catalyzed CO release from vascular smooth muscle cells provides a novel mechanism by which NO might modulate soluble guanylate cyclase and, thereby, vascular smooth muscle cell and platelet function.
由于最近的研究表明血管平滑肌细胞可合成两种不同的刺激鸟苷酸环化酶的气体，即一氧化氮（NO）和一氧化碳（CO），我们研究了这两种信号分子之间可能存在的调节相互作用。用NO供体硝普钠、S-亚硝基-N-乙酰青霉胺或3-吗啉代 sydnonimine处理大鼠主动脉平滑肌细胞，可使血红素加氧酶-1（HO-1）的mRNA和蛋白水平呈浓度和时间依赖性增加。放线菌素D和环己酰亚胺均能阻断NO刺激的HO-1 mRNA和蛋白表达。核转录实验表明，NO供体可使HO-1基因转录增加3至6倍。相反，NO供体对HO-1 mRNA的稳定性没有影响。用膜通透性cGMP类似物二丁酰cGMP和8-溴-cGMP孵育血管平滑肌细胞，未能诱导HO-1基因表达。用NO供体处理血管平滑肌细胞也刺激了CO的产生和释放，共孵育的血小板中细胞内cGMP水平的CO依赖性增加证明了这一点。最后，用白细胞介素-1β和肿瘤坏死因子-α孵育血管平滑肌细胞可诱导NO合成，同时也显著增加了HO-1蛋白水平。平滑肌细胞中细胞因子刺激产生的NO和HO-1蛋白均被NO合酶抑制剂甲基-L-精氨酸阻断。这些结果表明，外源性给予或内源性释放的NO可刺激血管平滑肌细胞中HO-1基因表达和CO产生。NO诱导血管平滑肌细胞中HO催化释放CO的能力提供了一种新机制，通过该机制NO可能调节可溶性鸟苷酸环化酶，从而调节血管平滑肌细胞和血小板功能。
