Coast J R, Romeo R M, Cassidy S S
Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas 75235-9034.
Respir Physiol. 1989 Mar;75(3):279-88. doi: 10.1016/0034-5687(89)90038-8.
This study was performed to assess the effect of pulmonary C-fiber stimulation with capsaicin on vascular resistance in the diaphragm. Nine dogs were anesthetized with pentobarbital sodium and were instrumented with right and left ventricular catheters. The left phrenic artery was isolated and perfused from an extracorporeal reservoir. Right ventricular capsaicin injections (5-20 micrograms/kg) caused significant decreases in phrenic perfusion pressure (-16%), systemic arterial pressure (-32%), and heart rate (-19%). Injection of identical doses of capsaicin into the left ventricle led to no significant changes in phrenic arterial perfusion pressure or systemic arterial pressure but a 10% decrease in heart rate. Bilateral cervical vagotomy eliminated the response to both right and left ventricular injection of capsaicin, as did administration of the autonomic ganglion blocker hexamethonium bromide. The results indicate that pulmonary C-fiber stimulation reflexly vasodilates vessels in the diaphragm.
本研究旨在评估用辣椒素刺激肺C纤维对膈肌血管阻力的影响。9只狗用戊巴比妥钠麻醉，并插入右心室和左心室导管。分离左膈动脉并从体外储液器进行灌注。右心室注射辣椒素（5 - 20微克/千克）导致膈灌注压显著降低（-16%）、体动脉压显著降低（-32%）和心率显著降低（-19%）。向左心室注射相同剂量的辣椒素导致膈动脉灌注压或体动脉压无显著变化，但心率降低10%。双侧颈迷走神经切断术消除了对右心室和左心室注射辣椒素的反应，自主神经节阻滞剂溴化六甲铵的给药也有同样效果。结果表明，肺C纤维刺激可反射性地使膈肌血管舒张。
