Bladder wall relaxation and its dependency on transmural pressure and infusion rate during cystometry--in vivo studies in the rat.

Cystometry at different infusion rates was performed in 7 rats in vivo. The bladders were furthermore allowed to relax from different transmural pressures. When distension of the bladder was moderate, relative relaxation was small and almost independent of transmural pressure and infusion rate. When distended to large volumes, however, there was a marked increase in bladder wall relaxation and the relaxation increased with increasing infusion rates. These findings indicate the importance of standardization of the cystometric procedure.