Karim F, Hainsworth R, Sofola O A, Wood L M
Circ Res. 1980 Jan;46(1):77-83. doi: 10.1161/01.res.46.1.77.
We stimulated the aortic chemoreceptors in dogs that were anesthetized with chloralose and artificially ventilated by perfusing the isolated aortic arch with venous blood. Inotropic responses were determined by measuring the maximum rate of change of left ventricular pressure (dP/dt max) with aortic pressure and heart rate held constant. Stimulation of the aortic chemoreceptors resulted in an average increase in heart rate of 14 +/- 2.0 beats/min (mean +/- SE) from 166 +/- 7.7 beats/min and an increase in dP/dt max of 501 +/- 85 mm Hg/sec from 3508 +/- 154 mm Hg/sec. These changes were statistically significant (P less than 0.001). The afferent pathway of the reflex was shown to be in the vagus nerves and the efferent pathway in the cardiac sympathetic nerves. In some of the dogs, the carotid chemoreceptors were also stimulated. This resulted in decreases in heart rate and dP/dt max of 48 +/- 24 beats/min and 795 +/- 142 mm Hg/sec. Thus we have shown that stimulation of aortic chemoreceptors evokes chronotropic and inotropic responses opposite to those evoked from stimulation of carotid chemoreceptors.
我们刺激了用氯醛糖麻醉并通过向离体主动脉弓灌注静脉血进行人工通气的犬的主动脉化学感受器。通过在主动脉压力和心率保持恒定的情况下测量左心室压力的最大变化率（dP/dt max）来确定变力反应。刺激主动脉化学感受器导致心率从166±7.7次/分钟平均增加14±2.0次/分钟（平均值±标准误），dP/dt max从3508±154毫米汞柱/秒增加501±85毫米汞柱/秒。这些变化具有统计学意义（P小于0.001）。反射的传入途径显示在迷走神经中，传出途径在心脏交感神经中。在一些犬中，也刺激了颈动脉化学感受器。这导致心率和dP/dt max分别降低48±24次/分钟和795±142毫米汞柱/秒。因此，我们已经表明，刺激主动脉化学感受器会引发与刺激颈动脉化学感受器所引发的变时性和变力性反应相反的反应。
