Erythropoietin receptor expression in the human urogenital tract: immunolocalization in the prostate, neurovascular bundle and penis

OBJECTIVE: To investigate whether the erythropoietin (EPO) receptor is expressed in human periprostatic (including the neurovascular bundles) and penile tissues, and define its distribution in these tissues, as the administration of exogenous EPO in cavernous nerve injury promoted the recovery of erectile function in a rat model. MATERIALS AND METHODS: Human prostate (six samples) and penile (two) tissue were collected and paraffin-embedded. Tissue was sectioned and processed for immunohistochemical studies using an antibody for the EPO receptor; immunolocalization was assessed using light microscopy. RESULTS: There was prominent staining for the EPO receptor in neuronal cell bodies of the periprostatic neurovascular bundles, and in the axons emanating from these ganglia. The glandular epithelium of the prostate also had weak staining. There was EPO receptor immunoreactivity in the penile specimens in the penile dorsal nerves, sinusoidal endothelium of the corpus cavernosum, and endothelial cells lining the dorsal veins and arteries. All slides processed with no primary antibody or blocking peptide showed no staining. CONCLUSIONS: EPO receptor expression was identified and localized in human penile tissues and in the periprostatic neurovascular bundles responsible for erectile function. This suggests a likely role for endogenous EPO within these tissues, and provides the rationale for its clinical use as a protective agent locally.