Influence of low dose dopamine on the heart rate and ventilatory responses to sustained isocapnic hypoxia.

Abstract

In awake humans, acute isocapnic hypoxia causes a rapid increase in both ventilation and heart rate. Although the acute ventilatory response is mediated primarily through a stimulatory drive from the carotid body, the heart rate response is more complex. There is apparently a heart rate depressing drive arising from the carotid bodies (CB), and a stimulation arising from a central effect of hypoxia, stimulation from vagal reflexes from the increased pulmonary ventilation and perhaps an increased drive from the aortic bodies (see ref. 1 for a review).