Brunner M J, Kligman M D
Department of Surgery, University of Maryland, Baltimore 21201.
J Appl Physiol (1985). 1993 Mar;74(3):1274-9. doi: 10.1152/jappl.1993.74.3.1274.
The purpose of this study was to determine whether baroreflex control of respiratory responses is diminished in hypertension. Ten dogs were made chronically hypertensive with use of a bilateral renal wrap technique. Eight sham-operated dogs served as normotensive controls. After the development of experimental hypertension, carotid baroreflex control of arterial pressure, heart rate, respiratory frequency, tidal volume, and ventilation was acutely assessed. Under pentobarbital anesthesia and with bilateral vagotomy, the carotid sinuses were isolated and perfused at controlled pressures. Before the carotid sinus region was manipulated, the mean arterial pressure was significantly higher (P < 0.005) in the hypertensive group (146.4 +/- 2.3 mmHg) than in the normotensive group (124.7 +/- 2.6 mmHg). The mean arterial pressures and heart rates measured at every level of carotid sinus pressure were significantly higher in the hypertensive group. Reflex gain of heart rate, but not mean arterial pressure, was significantly reduced in the hypertensive group. Respiratory frequency, tidal volume, and ventilatory responses to changes in carotid sinus pressure were significant and resulted in an approximately 40% reflex change in ventilation. These responses were not diminished in the hypertensive group. We conclude that respiratory baroreflex responses are preserved in experimental hypertension.
本研究的目的是确定高血压患者压力感受器对呼吸反应的控制是否减弱。使用双侧肾包裹技术使10只狗长期患高血压。8只假手术狗作为正常血压对照。在实验性高血压形成后，对颈动脉压力感受器对动脉血压、心率、呼吸频率、潮气量和通气的控制进行急性评估。在戊巴比妥麻醉和双侧迷走神经切断的情况下，分离颈动脉窦并在控制压力下进行灌注。在操作颈动脉窦区域之前，高血压组的平均动脉压（146.4±2.3 mmHg）显著高于正常血压组（124.7±2.6 mmHg）（P<0.005）。高血压组在每个颈动脉窦压力水平下测得的平均动脉压和心率均显著更高。高血压组心率的反射增益显著降低，但平均动脉压未降低。呼吸频率、潮气量以及对颈动脉窦压力变化的通气反应显著，导致通气反射性变化约40%。高血压组的这些反应并未减弱。我们得出结论，在实验性高血压中呼吸压力感受器反射反应得以保留。
