Effects of altitude acclimatization on rat myoglobin. Effect of viscosity and acclimatization on myoglobin reaction rates

¹ Biophysics Laboratories, Departments of Physics, Zoology and Entomology, Pennsylvania State University, University Park, Pennsylvania

Equipment and procedure used in the determination of myoglobin-oxygen reaction rate constants in viscous media are described briefly. The rate constants were determined for purified extracts of myoglobin from control and acclimatized rats over the viscosity range 0.87–53 centipoise. Glycerol-water mixtures were used as the viscous media. The reaction rates were found to vary with the viscosity of the suspending medium in a nonlinear fashion. No difference was observed in the reaction rates for acclimatized versus control rats using skeletal muscle extracts. A preliminary investigation of heart muscle extracts indicates a decrease in the oxygen association rate for the acclimatized rats. The significance of the kinetic data is discussed.