MUSCULAR CAVERNOUS SINGLE-CELL ANALYSIS IN PATIENTS WITH VENOOCCLUSIVE DYSFUNCTION

Enzymatically isolated smooth muscle cells of the corpora cavernosa ob tained from open biopsies of 15 patients, clinically nonresponding to papaverine/phentolamine and prostaglandin E(1) (PGE(1)) and classified by cavernosometry, were examined using the patch-clamp technique in t he whole-cell configuration mode simultaneously monitoring the intrace llular calcium concentration by means of the Ca2+-sensitive fluorescen ce dye FURA-II. It could be demonstrated that extracellularly applied PGE(1) induces smooth muscle relaxation by inhibition of voltage-depen dent L-type Ca2+ currents (58 +/- 8%). Compared to intact cavernous ti ssue (n = 5), the smooth muscle cells of 14/15 PGE(1) nonresponders ha d no evidence of functional disturbance. Due to intact smooth muscle c ells in most cases, etiology of venoocclusive dysfunction remains uncl ear.