AN IMPROVED METHOD FOR SIMULTANEOUS MEASUREMENT OF OXYGEN CONSUMPTION AND MECHANICAL ACTIVITY OF ISOLATED MUSCLE PREPARATIONS

An improved method for the simultaneous determination of mechanical activity and oxygen consumption of isolated muscle preparations is described. As in conventional procedures the organ bath was perfused at a constant rate and the changes in oxygen concentration in the perfusate were followed continuously by a polarographic method. The sensitivity and stability of the oxygen electrodes were increased considerably by using platinum wires of rather large diameter (0.3 to 0.5 mm), extremely thin teflon membranes (6 μ) and agar-agar stabilized KCl-solution as the filling medium. Due to the improved properties of these electrodes the perfusion rate could be increased by a factor of 10 to 30 as compared to previous methods. Therefore, the oxygen supply to the isolated muscle preparation was improved (resulting in a better functional state) and the time of resolution of changes in oxygen concentration in the perfusion medium was reduced (allowing a better correlation of the oxygen consumption to mechanical activity. © 1968 Springer-Verlag.