Adventitia-dependent relaxations of canine basilar arteries transduced with recombinant eNOS gene.
Adventitia-dependent relaxations of canine basilar arteries transduced with recombinant eNOS gene.
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DOI：
10.1152/ajpheart.1999.276.6.h1846
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发表时间：
1999-06
期刊：
影响因子：
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通讯作者：
M. Tsutsui;H. Onoue;Y. Iida;Leslie A. Smith;T. O’Brien;Z. Katusic
中科院分区：
文献类型：
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作者：
M. Tsutsui;H. Onoue;Y. Iida;Leslie A. Smith;T. O’Brien;Z. Katusic
我们最近报道了重组内皮型一氧化氮合酶（eNOS）基因在外膜成纤维细胞中的表达恢复了无内皮犬脑动脉对缓激肽的体内和体外反应中NO的形成。本研究旨在进一步表征可以激活脑动脉外膜中表达的重组eNOS酶的刺激物。为了刺激重组eNOS，我们使用血清（0.1-10%）、P物质（10-11-3 × 10-9 M）和ANG II（10-7-10- 5 M），因为它们增加成纤维细胞中的细胞内钙浓度。将犬基底动脉剥脱内皮的节段与编码β-半乳糖苷酶基因或eNOS基因的腺病毒载体在37°C下孵育30分钟。24 h后，分别用等长收缩力记录法和放射免疫法检测内皮型一氧化氮合酶（eNOS）和β-半乳糖苷酶（β-galactosidase，β-galactosidase）的血管活性和环鸟苷酸（cGMP）的生成。在对照动脉和β-半乳糖苷酶基因转导的动脉中，血清引起浓度依赖性收缩，而在重组eNOS基因转导的动脉中，血清产生浓度依赖性舒张。P物质和ANG II对对照动脉和β-半乳糖苷酶动脉的血管张力没有影响，但引起浓度依赖性舒张以及eNOS动脉中cGMP水平的显著增加。NOS抑制剂NG-硝基-L-精氨酸甲酯可阻断这种舒张作用。化学处理或机械失活外膜功能显着衰减P物质诱导的舒张和ANG II诱导的舒张。这些结果表明，血清，P物质，和血管紧张素II引起血管外膜依赖性舒张表达重组eNOS基因的脑动脉。这种血管舒张机制可能对预防和治疗以NO生物利用度降低为特征的血管疾病（如脑血管痉挛）具有有益作用。
We recently reported that expression of recombinant endothelial nitric oxide (NO) synthase (eNOS) gene in adventitial fibroblasts restores NO formation in canine cerebral arteries without endothelium in response to bradykinin ex vivo and in vivo. The present study was designed to further characterize the stimuli that can activate recombinant eNOS enzyme expressed in the adventitia of cerebral arteries. To stimulate recombinant eNOS, we used serum (0.1-10%), substance P (10-11-3 × 10-9 M), and ANG II (10-7-10-5M) because they increase intracellular calcium concentrations in fibroblasts. Endothelium-denuded segments of canine basilar arteries were incubated with an adenoviral vector encoding β-galactosidase gene or eNOS gene for 30 min at 37°C. After 24 h, vasomotor activity and cGMP formation in eNOS or β-galactosidase arteries were examined by isometric force recording and by radioimmunoassay, respectively. In control arteries and β-galactosidase gene-transduced arteries, serum caused concentration-dependent contractions, whereas in recombinant eNOS gene-transduced arteries, serum produced concentration-dependent relaxations. Substance P and ANG II had no effect on vascular tone in control and β-galactosidase arteries but caused concentration-dependent relaxations as well as a significant increase in cGMP levels in eNOS arteries. These relaxations were blocked by the NOS inhibitor N G-nitro-l-arginine methyl ester. Chemical treatment or mechanical inactivation of adventitial function significantly attenuated substance P-induced relaxations and ANG II-induced relaxations. These findings demonstrate that serum, substance P, and ANG II cause adventitia-dependent relaxations in cerebral arteries expressing the recombinant eNOS gene. This mechanism of vasodilatation may have beneficial effects in the prevention and treatment of vascular disorders characterized by the diminished bioavailability of NO, such as cerebral vasospasm.