Significance of K(ATP) channels, L-type Ca²⁺ channels and CYP450-4A enzymes in oxygen sensing in mouse cremaster muscle arterioles in vivo

ATP-sensitive K⁺ channels (KATP channels), NO, prostaglandins, 20-HETE and L-type Ca²⁺ channels have all been suggested to be involved in oxygen sensing in skeletal muscle arterioles, but the role of the individual mechanisms remain controversial. We aimed to establish the importance of these mechanisms for oxygen sensing in arterioles in an in vivo model of metabolically active skeletal muscle. For this purpose we utilized the exteriorized cremaster muscle of anesthetized mice, in which the cremaster muscle was exposed to controlled perturbation of tissue PO₂.