Effects of acid‐base changes on rabbit urinary bladder contractility

Alterations in the pH of the in vitro bathing medium can effect intracellular pH and thus alter the contractile response of smooth muscle preparations to various forms of stimulation. The mucosal surface of the urinary bladder provides a barrier to most solutes within the bladder. The purpose of this study was to determine if alterations in the intravesical pH would affect the contractile response to field stimulation. The in vitro whole rabbit bladder model was used to study the effect of changing intravesical pH on bladder contractility. Contrary to previous studies on isolated muscle strips, the results of the present study show that under different pH conditions (pH 4.0–8.0), no significant changes were observed in intravesical pressure generation with field stimulation, nor in the rate of the pressure generation. An intact bladder mucosa appears to be an effective barrier against the physiological effects of altered intravesical pH on bladder smooth muscle contraction.