Thermoregulatory response to hypoxia after inhibition of the central heme oxygenase-carbon monoxide pathway

(1) Centrally acting carbon monoxide (CO) seems to play thermoregulatory ac tions, but no report exists about its role in hypoxia-induced anapyrexia. ( 2) CO arises from the catabolism of heine by heme oxygenase (HO), an enzyme that is overexpressed during hypoxia. Thus, we tested the hypothesis that the central HO CO pathway modulates hypoxia-induced anapyrexia by means of intracerebroventricular injection of the HO inhibitor ZnDPBG. (3) Core temp erature (T-C) of awake rats was determined by biotelemetry. ZnDPBG did not alter basal T-c, but it exacerbated hypoxia-induced anapyrexia, indicating that the central HO CO pathway is a modulator of hypoxia-induced anapyrexia . probably preventing excessive decreases in T-c. (C) 2001 Elsevier Science Ltd. All rights reserved.