Journal of Applied Physiology, Vol 40, Issue 3 324-328, Copyright © 1976 by American Physiological Society
Chronic carbon monoxide poisoning: effects on performance of the isolated right ventricle
L. B. Bugaisky and D. G. Penney
Rats were exposed continuously for 21-35 days to 500 ppm carbon monoxide
(37.4-39.2% HbCO). Aerobic resting force (RF)-active isometric twitch force
(AF) curves of isolated right ventricle preparations were constructed at 27
degrees C. CO and control groups are nearly identical when expressed as
percent of maximal AF over the range of RF used. There are no significant
differences in AF either at the peak of the curve or at RF = 1 g. During 15
min of anoxia AF declines at both RF's used. Increased anoxic tolerance is
apparent in all CO preparations when anoxic AF is plotted as percent of
preanoxic AF. The effect is most marked at RF = 1 g, where time to one-half
preanoxic AF is 12.6 +/- 0.9 vs.9.3 +/- 0.8 min for CO-exposed and
controls, respectively. However, no significant differences in "absolute"
AF are seen between the groups at either level of RF at any minute during
anoxia. Aerobic recovery of CO preparations is markedly enhanced at 1 g RF.
Anoxic tolerance and aerobic recovery differences, however, are smaller at
the peak of the RF-AF curve. Effects on time to peak AF and maximal rate of
rise of AF are not marked at either level of RF in CO preparations.
