Fig. 2.

Assessment of morphologic markers of the angiogenic process before and after exercise training in skeletal muscle biopsies of COPD patients and SHS. a-c Transmission electron micrographs focused on morphologic markers of angiogenesis, shown with black arrows: a intraluminal endothelial (EC) folding, b abluminal EC sprout, and c pericyte/endothelium (Pc/EC) interdigitations. d-f) Semi-quantitative analysis of the occurrence of intraluminal EC folding (d), abluminal EC sprouts (e), and Pc/EC interdigitations (f) on transmission electron micrographs. g, h Quantitative analysis of endothelial nucleus density (g) and pericyte coverage (h) on transmission electron micrographs. Lum: lumen; EC: endothelium; BM: basement membrane; Pc: pericyte. Data are presented as mean ± SE. Linear mixed-effect model: T: Time effect; G: Group effect; GxT: Group x Time interaction. Scale bar: 500 nm