PECAM1 and sexually transmitted disease: To verify whether angiogenesis occurs in the VD model, we performed Immunofluorescence validation on CD31, a classical angiogenesis marker, and found that the expression levels of CD31 in the hippocampus of rats in the VD group were significantly downregulated (Figures 8A,G), indicating the inhibition of angiogenesis phenotype in the VD rats.