Implications of caveolae in testicular and epididymal myoid cells to sperm motility.

Seminiferous tubules of the testis and epididymal tubules in adult rodents are enveloped by contractile myoid cells, which move sperm and fluids along the male reproductive tract. Myoid cells in the testis influence Sertoli cells by paracrine signaling, but their role in the epididymis is unknown. Electron microscopy revealed that elongated myoid cells formed several concentric layers arranged in a loose configuration.

Alterations in the testis and epididymis associated with loss of function of the cystatin-related epididymal spermatogenic (CRES) protein.

Cystatin-related epididymal spermatogenic protein (CRES) or cystatin 8 (Cst8 gene) is a member of the cystatin superfamily of cysteine protease inhibitors. It differs from typical cystatins because it lacks consensus sites for cysteine protease inhibition and exhibits reproductive-specific expression. In the present study, we examined CRES expression within the testes, efferent ducts, and epididymides of normal mice by light microscope immunolocalization.