Matsumoto T, Okamura T, Kinoshita M, Toda N
Department of Pharmacology, Shiga University of Medical Sciences, Ohtsu, Japan.
Eur J Pharmacol. 1993 Jun 11;237(1):31-7. doi: 10.1016/0014-2999(93)90089-z.
In helical strips of dog coronary arteries contracted with prostaglandin F2 alpha, relaxant responses to atrial natriuretic peptide (ANP), nitric oxide (NO), nitroglycerin and 8-bromo cyclic GMP were markedly inhibited or abolished by treatment with a high concentration of sodium nitroprusside, whereas the responses to beraprost and papaverine were not influenced. A similar suppression of the responses to ANP, NO, and sodium nitroprusside was observed after treatment with nitroglycerin. The relaxations induced by NO and nitroglycerin were abolished by methylene blue and oxyhemoglobin, whereas the response to ANP was not influenced. The sodium nitroprusside-induced relaxation was significantly potentiated by methylene blue but was abolished by oxyhemoglobin. The increase in cyclic GMP caused by ANP and nitroglycerin was not influenced by treatment with sodium nitroprusside, despite the fact that the responses to ANP and nitroglycerin were suppressed. It can be concluded that ANP and nitroglycerin or sodium nitroprusside share the same mechanism of action on intracellular processes occurring after the synthesis of cyclic GMP in dog coronary artery smooth muscle cells and that cross-tachyphylaxis between nitroglycerin, sodium nitroprusside, and ANP in the mechanical response is not associated with an impaired production of cyclic GMP.
在用前列腺素F2α收缩的犬冠状动脉螺旋条中，高浓度硝普钠处理可显著抑制或消除对心房利钠肽（ANP）、一氧化氮（NO）、硝酸甘油和8-溴环鸟苷酸的舒张反应，而对贝拉前列素和罂粟碱的反应则不受影响。用硝酸甘油处理后，观察到对ANP、NO和硝普钠的反应有类似的抑制作用。NO和硝酸甘油诱导的舒张反应被亚甲蓝和氧合血红蛋白消除，而对ANP的反应不受影响。硝普钠诱导的舒张反应被亚甲蓝显著增强，但被氧合血红蛋白消除。尽管对ANP和硝酸甘油的反应受到抑制，但硝普钠处理并未影响ANP和硝酸甘油引起的环鸟苷酸增加。可以得出结论，ANP与硝酸甘油或硝普钠在犬冠状动脉平滑肌细胞中环鸟苷酸合成后发生的细胞内过程具有相同的作用机制，并且硝酸甘油、硝普钠和ANP在机械反应中的交叉快速耐受性与环鸟苷酸生成受损无关。
