The Harmful Effects of Superoxide Radical and the Protective Effect of Ginseng Saponin on Rat Whole Bladder Contractility / 대한비뇨기과학회지

ABSTRACT

PURPOSE: We investigated the effects of the superoxide radical on rat whole bladder contractility with duroquinone (superoxide radical generator, Dq) and diethyldithiocarbamate (superoxide dismutase inhibitor, DETCA), and the effects of ginseng saponin (GS) against superoxide radical injury. MATERIALS AND METHODS: Isometric tension changes of isolated rat whole bladders were recorded in an organ bath using a force transducer. The acute effects of Dq and Dq preincubated with DETCA were assessed on resting tension, electrical field stimulation, and bethanechol-, ATP-, and KCl-induced contraction. The effects of Dq and Dq preincubated with DETCA in the presence of sodium nitroprusside and GS were investigated. RESULTS: The resting tension of the muscle was not changed by Dq and Dq preincubated with DETCA. Dq had a harmful effect on only ATP- and KCl-induced detrusor contraction, whereas Dq pretreated with DETCA attenuated the induction of detrusor contraction which was reduced in response to the exogenous NO including GS. In the presence of L-NAME, the effects of GS reduced the Dq-induced inhibition on the detrusor contractility. CONCLUSIONS: It is suggested that the superoxide radical may be the cause of voiding difficulty. GS, as a NO synthesis stimulator, seems to act as a scavenger of the superoxide anion. However further study on the effect of each subfraction of GS is needed for clinical application.