Identification of Endothelial Progenitor Cells in the Corpus Cavernosum in Rats

The vascular wall resident progenitor cells seem to serve as a local reservoir of cells for vascular repair. It was hypothesized that the corpus cavernosum may contain vascular wall endothelial progenitor cells (EPCs). In this study, we investigated the identification and localization of EPCs in the corpus cavernosum in a rat model. Adult male Sprague-Dawley rats were used to isolate EPCs from corpora cavernosum. To verify the existence and localization of EPCs, EPC-specific markers (CD34, Flk-1, and VE-cadherin) were evaluated by flow cytometric analysis and confocal microscopy. The EPC markers were mainly expressed in the cavernosal sinusoidal endothelial space. EPC-marker-positive cells made up about 3.31% of the corpus cavernosum of normal rat by FACS analysis. As shown by confocal microscopy, CD34(+)/Flk-1(+) and CD34(+)/VE-cadherin(+) positive cells existed in the corpus cavernosum. Our findings imply that regulation of corpus cavernosal EPCs may be a new therapeutic strategy in the treatment of erectile dysfunction.