Effects of chronic exposure to cold or hypoxia on ventricular weights and ventricular myoglobin concentrations in guinea pigs during growth
Van Bui, M.; Banchero, N.
Pflugers Archiv European Journal of Physiology 385(2): 155-160
1980
ISSN/ISBN: 0031-6768 PMID: 7190274 Document Number: 165137
Male guinea pigs were continuously exposed to 5.degree. C for 2-18 wk (BW of the right and the left ventricles were measured. In all animals total heart weights (THW), RVW and LVW were linearly related to BW. In the control animals, ventricular Mb increased with BW for 2-3 wk after birth, but remained unchanged therafter. In the 5.degree. C animals, after 4 wk of exposure, Mb in the right and the left ventricles was significantly higher than that of the controls. THW was significantly higher in the 5.degree. C animals. This cold-induced cardiac hypertrophy was due to right and left ventricular hypertrophy. In hypoxia-acclimated animals, after 14 wk of exposure to PO2 = 80 mm Hg, the Mb of the RV was significantly higher than that of the controls; there was no significant difference between the Mb of the LV of the control and hypoxic animals. THW was significantly higher in the hypoxic guinea pigs than in the controls or the 5.degree. C animals. The hypoxia-induced cardiac hypertrophy was due to a marked right ventricular hypertrophy, while LVW was significantly lower in the hypoxic animals than in the controls.