Figure 1. AMPK-dependent regulation of hypoxic pulmonary vasoconstriction.

A, from left to right: brightfield image of an isolated and fixed pulmonary arterial smooth muscle cell; z section showing immuno-labelling for the AMPK-α1 catalytic subunit isoform (green) and the DAPI labelled nucleus (blue); 3D reconstruction. B, schematic diagram describing the role of AMPK in HPV: hypoxia inhibits mitochondrial oxidative phosphorylation, which leads to an increase in the AMP/ATP ratio, AMPK activation, consequent cADPR-dependent SR Ca²⁺ release in pulmonary arterial smooth muscle and HPV.