Ohsumi H, Sakamoto M, Yamazaki T, Okumura F
Department of Anesthesiology, National Cardiovascular Center, Osaka, Japan.
Am J Physiol. 1989 Mar;256(3 Pt 2):R625-31. doi: 10.1152/ajpregu.1989.256.3.R625.
The effects of intravenous administration of fentanyl on carotid sinus baroreflex control of hemodynamics were investigated in chronically instrumented rabbits. Carotid sinus baroreflex was assessed by bilateral carotid occlusion (BCO), and the responses of mean arterial pressure (MAP), heart rate (HR), mean ascending aortic flow (MAF), and total peripheral resistance (TPR) were obtained. Hemodynamic responses to BCO were examined with cumulative doses of 5, 10, and 15 micrograms/kg of fentanyl. Fentanyl did not affect MAP and TPR but reduced HR and MAF dose dependently. Fentanyl did not attenuate the MAP response to BCO significantly. In contrast, fentanyl significantly attenuated the TPR response from 0.126 +/- 0.003 to 0.104 +/- 0.005 mmHg.min-1.ml-1 and augmented the HR response from 31 +/- 2 to 47 +/- 3 beats/min in the conscious state and at 15 micrograms/kg of fentanyl, respectively. The administration of atropine after the fentanyl attenuated MAP and HR responses to 79.9 and 27.7% of those of 10 micrograms/kg of fentanyl, respectively. We suggest that these dissociated hemodynamic responses reflect the vagotonic and sympatholytic effects of fentanyl on the baroreflex pathways.
在长期植入仪器的家兔中研究了静脉注射芬太尼对颈动脉窦压力反射控制血流动力学的影响。通过双侧颈动脉闭塞（BCO）评估颈动脉窦压力反射，并获得平均动脉压（MAP）、心率（HR）、平均升主动脉血流量（MAF）和总外周阻力（TPR）的反应。用累积剂量为5、10和15微克/千克的芬太尼检查对BCO的血流动力学反应。芬太尼不影响MAP和TPR，但剂量依赖性地降低HR和MAF。芬太尼对BCO引起的MAP反应无明显减弱作用。相反，在清醒状态下，当芬太尼剂量为15微克/千克时，芬太尼可使TPR反应从0.126±0.003显著减弱至0.104±0.005 mmHg·min⁻¹·ml⁻¹，并使HR反应从31±2次/分钟增加至47±3次/分钟。芬太尼给药后给予阿托品，可使MAP和HR反应分别减弱至10微克/千克芬太尼反应的79.9%和27.7%。我们认为这些分离的血流动力学反应反映了芬太尼对压力反射通路的迷走神经兴奋和交感神经抑制作用。
