Second Pathways in the Pathophysiology of Ischemic Priapism and Treatment Alternatives

Abstract

To evaluate the early therapeutic alternatives such as bosentan, an endothelin receptor blocker, theophylline, an adenosin receptor blocker, and a nonselective phosphodiesterase enzyme inhibitor, zinc protoporphyrin (ZnPP), a heme oxygenase 1 inhibitor, for the therapy of ischemic priapism in the rat models. Twenty-four Sprague-Dawley rats were randomly divided into 4 equal groups: control group, ZnPP group, bosentan group, and theophylline group. Erection was provided by vacuum constriction method and maintained for 4 hours for achieving the priapism in all groups. The rats in the control group were administered 1 mL/kg saline intraperitoneally (ip). The rats in group 2 were administered 25 mg/kg ZnPP ip. The rats in group 3 were administered 0.25 mg/kg bosentan ip. The rats in group 4 were administered 100 mg/kg theophylline ip. Six rats from each group were decapitated after 6 hours of drug administration. Then endothelin 1, adenosine deaminase, heme oxygenase 1 enzymatic activity, and apoptosis index in the cavernous tissues were estimated. Cavernous tissue endothelin 1, adenosine deaminase, heme oxygenase 1 enzymatic activity levels, and apoptosis index were significantly decreased in bosentan, theophylline, and ZnPP-treated rats compared with the controls. Inhibition of priapism induced apoptosis with bosentan, theophylline, and ZnPP seems promising on preserving erectile function.