Read Hypoxic Pulmonary Vasoconstriction
A short NSEB read on hypoxic pulmonary vasoconstriction, followed by the linked original question(s).
Hypoxic Pulmonary Vasoconstriction is the central idea in this question pattern. Identify the condition in the stem before applying the method below.
Core idea
Low alveolar oxygen locally constricts nearby pulmonary arterioles, diverting blood toward better-ventilated regions. In pulmonary arterial smooth muscle, reduced mitochondrial ROS under hypoxia closes oxygen-sensitive K⁺ channels; depolarisation then opens voltage-gated Ca²⁺ channels, raising intracellular calcium and causing contraction. Restoring oxygen reverses the signal.
ROS decrease to potassium closure to calcium rise
Hypoxia reduces mitochondrial reactive oxygen species, closes oxygen-sensitive potassium channels, depolarises the membrane, opens voltage-gated calcium channels and raises intracellular calcium.
OlympIQ exam lens
- ✓Low alveolar oxygen locally constricts nearby pulmonary arterioles, diverting blood toward better-ventilated regions.
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