CALB2 and pulmonary artery enlargement: In contrast, the overlay of CD31-immunoreactive and calretinin-immunoreactive 3D maps confirmed that several calretinin-positive interneurons were closely associated with perforating microvessels (Fig. 6C,F, arrows; Movie 1) and that PAE significantly reduced the density of calretinin-positive interneurons (p = 0.0159, controls n = 5 for control and PAE groups, U = 1, Mann–Whitney test) and the number of calretinin-positive interneurons associated to perforating vessel (p = 0.0159, controls n = 5 control and PAE groups, U = 1, Mann–Whitney test; Fig. 6H).