Glucose metabolism and bicarbonate turnover in dystrophic mice

Abstract

Hereditarily dystrophic and littermate control mice of the Bar Harbor strain 129 were injected with bicarbonate-C¹⁴ to compare rates of turnover of the body bicarbonate compartments. A separate group of dystrophic mice was also injected with glucose-U-C¹⁴ to study the turnover and oxidation to CO₂ of body glucose. The total glucose pool size was also measured in four dystrophic mice and was found to be 50% greater per unit body weight than that of the previously published mean value for control mice. Since the plasma glucose concentration was the same in both groups, the increased glucose compartment size appears to reflect a relative increase in extracellular space. Specific activity-time curves of respiratory C¹⁴O₂ were identical in both groups of mice after intravenous injection of bicarbonate-C¹⁴. Average values of plasma and whole body glucose specific activity 5–15 min after injection of glucose were lower than, but not significantly different from, those reported previously for control mice. The rate of formation of C¹⁴O₂ from glucose-C¹⁴ was at least as fast in dystrophic mice as in controls. The data indicate that the enzymatic pathways involved in glycolysis, the citric acid cycle, glucogenesis, and gluconeogenesis are functionally active in this disease.