[Effect of inhibition of glycolysis and myoendothelial electrical coupling on contractile responses of pulmonary artery and aorta during hypoxia in rats].
The effects of blockade of glycolysis on the contractile activity of isolated vascular rings of both the pulmonary artery and, the thoracic aorta were studied under hypoxia in intact, denuded vessels and those with blocked myoendothelial electrical coupling. The blockade of glycolysis led to a reversion of a hypoxic contraction in the pulmonary artery but had no effect on hypoxic dilatation of the aorta. Hypoxic constriction of the pulmonary artery was abolished after denudation and stayed unchanged at the following blockade of glycolysis. Moreover, blockade of glycolysis had no effect on the hypoxic responses of the pulmonary artery after blockade of the myoendothelial gap junctions. The data suggest that hypoxic contraction of the pulmonary artery is endothelium-dependent, in contrast to the hypoxic dilatation of the aorta. It is likely that glycolysis in endothelial cells and myoendothelial gap junctions contribute to hypoxic pulmonary vasoconstriction due to formation and conduction the depolarizing electrical signals from endothelial cells to smooth muscles causing their contraction under hypoxia.
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001013:Aorta, Thoracic / Q000502:physiology*; D001685:Biological Factors / Q000502:physiology; D015687:Cell Hypoxia / Q000502:physiology; D004730:Endothelium, Vascular / Q000502:physiology*; D005260:Female; D006019:Glycolysis / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000502:physiology; D011651:Pulmonary Artery / Q000502:physiology*; D051381:Rats; D014661:Vasoconstriction
D001685:Biological Factors; C067410:endothelium-dependent hyperpolarization factor