PRRT2 and diabetes mellitus: To identify the PKC isoform responsible for the endothelial impairment related to diabetes in the human corpus cavernosum, the effects of the specific inhibitor of the PKCβ2 isoform CGP53353 (0.3 μM) on endothelium-dependent relaxations in response to Ach were evaluated in CC strips and PRA segments from patients with diabetic ED.