Category Archives: Vasoconstriction

Canadian Neighbor Pharmacy: The Microscopic Site of Hypoxic Vasoconstriction

hypoxia receptorSince the effect of alveolar hypoxia is local and is predominantly on the small muscular pulmonary arteries, the next problem is to localize the “hypoxia receptor” across the thickness of the alveolar-vascular barrier. To do this we must go back to the basic anatomy of the pulmonary arterial wall. Figure 3 showed a small muscular pulmonary artery adjacent to a bronchiole in a dog lung. The wall of the vessel is thin, averaging about 10 percent of the luminal radius. The vessel illustrated has a radius of 150 |x. Thus, its wall is about 15 |x thick, separating alveolar gas from mixed venous blood.