SELECTIVE PHARMACOLOGICAL MANIPULATION OF THE SMOOTH-MUSCLE TISSUES OF THE GENITOURINARY TRACT - EXPERIMENTAL AND CLINICAL-STUDIES

Due to the limited therapeutic effectivity and possible significant sy stemic side effects, pharmacological treatment options for ureteral co lics, motor urge incontinence and erectile dysfunction are sparse. The aim of our studies was to examine in vitro and in vivo selective phar macological manipulation of genitourinary smooth muscle tissue by phos phodiesterase-inhibitors (PDE) or potassium-channel-openers (PCO). Cha racterization of the PDE by molecular biology showed the presence of P DE I, II, IV and V (ureter), III, IV and V (corpus cavernosum), I, II, III, IV and V(human detrusor). In vitro and in vivo, inhibition of PD E IV showed the most pronounced relaxing effect on ureteral tissue; wh ereas inhibition of PDE III and V was most effective in relaxing caver nous tissue. Inhibition of PDE I showed the most pronounced relaxing e ffect on bladder tissue in vitro and in vivo. A selective effect of th e PCO on ureteral tissue was shown in vitro, but was less obvious in v ivo. Our studies suggest a promising therapeutic potential for the use of selective PDE inhibitors in ureteral colics, detrusor instabilitie s and erectile dysfunction.