Hood J S, McMahon T J, Kadowitz P J
Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA 70112.
Eur J Pharmacol. 1991 Sep 4;202(1):121-4. doi: 10.1016/0014-2999(91)90265-r.
Pulmonary vasodilator responses to the K+ATP channel opener, RP 52891, were investigated in the intact-chest cat under constant flow conditions. When pulmonary vascular tone was increased with U46619, intralobar injections of RP 52891 caused dose-related decreases in lobar arterial and systemic arterial pressures without altering left atrial pressure. RP 52891 was more potent than pinacidil but less potent than cromakalim in dilating the pulmonary vascular bed. Pulmonary vasodilator responses to RP 52891, cromakalim and pinacidil, but not to acetylcholine, nitroprusside or isoproterenol, were blocked by glibenclamide. These data demonstrate that RP 52891 has potent pulmonary vasodilator activity in the cat and suggest that responses are due to opening of a glibenclamide-sensitive K+ATP channel.
在恒流条件下，对开胸猫研究了肺血管对钾离子通道开放剂RP 52891的舒张反应。当用U46619增加肺血管张力时，叶内注射RP 52891可引起叶动脉和体动脉血压呈剂量相关下降，而不改变左心房压力。在舒张肺血管床方面，RP 52891比吡那地尔更有效，但比克罗卡林效力稍弱。格列本脲可阻断肺血管对RP 52891、克罗卡林和吡那地尔的舒张反应，但不阻断对乙酰胆碱、硝普钠或异丙肾上腺素的反应。这些数据表明，RP 52891在猫中具有强大的肺血管舒张活性，并提示其反应是由于格列本脲敏感的钾离子通道开放所致。
