Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Raising arterial potassium ([K+]a) from ca. 3.5 to 6.5 mM, as occurs in heavy exercise, excites the arterial chemoreceptors and ventilation (VE) in anaesthetised cats. We have previously shown that the excitation of chemoreceptors by potassium is enhanced by hypoxia and abolished by hyperoxia, and here we show, in decerebrate cats, that the potassium-induced increase in VE is also abolished by hyperoxia. 100% oxygen was given abruptly in hypoxia (PETO2 ca. 50 Torr), with inspired gas tensions adjusted to give the same PETO2 and PETCO2 values before all tests on a given animal. Intravenous infusions of 150 mM KCl, which raised [K+]a from 3.9 +/- 0.3 mM to 7.4 +/- 0.3 mM (mean +/- SE), always excited hypoxic VE (42 +/- 8%; P less than 0.01). Hyperoxia, given during KCl infusion, reduced VE to a value not significantly greater (P greater than 0.27) than the hyperoxic value obtained before infusion. These results show that: (i) VE reflects the responses of chemoreceptors to K+, (ii) that abrupt hyperoxia removes the potassium-induced ventilatory drive, and (iii) that, in our experiments, K+ appears to have excited VE only via the peripheral chemoreceptors.

Original publication

DOI

10.1016/0034-5687(91)90119-4

Type

Journal article

Journal

Respir Physiol

Publication Date

05/1991

Volume

84

Pages

223 - 230

Keywords

Animals, Cats, Chemoreceptor Cells, Decerebrate State, Female, Infusions, Intravenous, Lung, Male, Oxygen, Physical Exertion, Potassium, Pulmonary Artery, Pulmonary Gas Exchange, Respiration