Microvascular and interstitial pO₂ measurements in the skeletal muscle by phosphorescence quenching technique

To clarify the oxygen transport across the microvessel and oxygen distribution in the skeletal muscle, we have newly designed an intravital laser microscopy with oxygen-dependent quenching of phosphorescence technique. This microscopy was applied to microvascular and tissue pO₂ measurements in the rat cremaster muscle. From these measurements, we found a significant reduction of pO₂ levels in arterioles of different orders and large pO₂ gradients at the interface between blood and tissue, in which suggest that O₂ consumption of the smooth muscle and/or endothelium in the skeletal muscle arteriole might be high.