The physiological function of myoglobin is reviewed briefly with the emphasis of the "oxygen buffer" and facilitation of oxygen diffusion.
The techniques, employed by authors, for persuing the absorption changes of myoglobin and cytochrome aa3 with the hemoglobin-free perfused rat heat are presented, where the oxygenation-deoxygenation of myoglobin and redox-change of cytochrome aa3 are successfully measured with the millisecond time-range during the 1 cycle of contraction-relaxation. From the detailed analysis of the absorption change of both components during the each heat beat, it is concluded that myoglobin in the cardiac tissue acts as oxygen buffer to iron out the fluctuation of intracellular oxygen concentration arising from the contraction-relaxation cycle.
