Figure 4. 5-MTP increases endothelial proliferation following arterial denudation. Femoral arteries were harvested 4 d after injury. (A–C) Elastin stain of longitudinal vessel sections. Arrows, internal elastic lamina (IEL); med, media. (D–F) CD31 staining for ECs. Arrowheads, CD31-positive brown cells. (G–I) BrdU immunostaining for proliferating cells. Arrowheads, BrdU-positive brown nuclei. Dashed line, external elastic lamina. (J–L) Double immunostaining of CD31 (blue) and BrdU (brown). Arrowheads, double-positive cells. (M) Quantitation of BrdU-positive cells on the luminal surface of arteries from vehicle (n=10) and 5-MTP-treated mice (n=8; *p<0.002). (N) TNF-α decreased HUVEC proliferation induced by VEGF (n=4 each, *p<0.001). 5-MTP rescued TNF-α-decreased endothelial proliferation (n=4 each, #p<0.008).