Coexpression of different cytokeratins, vimentin and desmin in the rete testis and epididymis in the dog.

The expression patterns of low and high molecular weight cytokeratins (LCK and HCK) vimentin and desmin were investigated by immunocytochemistry in the rete testis and epididymis in the dog. The epithelium of the rete testis displayed coexpression of LCK, vimentin and desmin. The epithelium of the efferent ductules was composed of ciliated and nonciliated cells; the ciliated cells expressed LCK strongly. The epithelium of the epididymal duct was composed of principal, apical and basal cells. Principal cells in the duct of the head of the epididymis displayed LCK and vimentin, with a predominance of LCK in the apical cytoplasmic regions and vimentin in the basal portions of the cells. Expression of vimentin in the principal cells decreased towards the body of the epididymis and disappeared in the tail region, where LCK remained unchanged. Apical cells of the epididymal duct expressed LCK. Basal cells in the duct of the head and body of the epididymis showed LCK and those of the duct of the body of the epididymis also HCK expression.