Influence of reduced carotid body drive during sustained hypoxia on hypoxic depression of ventilation in humans.

摘要: To evaluate whether the intact hypoxic drive from carotid bodies during sustained hypoxia is required for generation of depression ventilation (VE), 16 volunteers were exposed to two consecutive periods isocapnic (first period 20 min; second 5 end-tidal PO2 45 Torr) separated by 6 min normoxia. In study A, saline was given. B, 3 micrograms.kg-1.min-1 i.v. dopamine (DA), a body inhibitor, given first exposure followed normoxia and exposure. C, with DA preceded without DA. The peak VE (PHV) in A approximately 100% above normoxic VE. After hypoxia, declined 60% PHV only PHV. We relate this delayed recovery "ongoing" effects depression. During infusion, changes due insignificant (study B). B not different after air breathing studies C. This indicates that suppressed complete within min. Our results show despite central absence ventilatory intravenous prevented subsequent response.