We investigated the effects of AH-9700 (1-[2-(3,4-dihydro-6,7-dimethyl-2-naphthalenyl)ethyl] pyrrolidine fumarate; a novel sigma receptor ligand), (+)-pentazocine and 1,3-di-o-tolylguanidine (DTG) (two typical sigma receptor ligands), and oxybutynin (a currently used anti-pollakiuria drug) on cystometrograms in anesthetized rats with 30% acetone-induced cystitis. Compared to sham-treated rats, acetone-treated cystitis models exhibited an increase in urinary frequency during continuous filling cystometry. Intravenous administration of AH-9700 (1-5 mg/kg), (+)-pentazocine or DTG to the rats with cystitis dose-dependently prolonged micturition intervals and increased the micturition threshold pressure. Oxybutynin (1 mg/kg. i.v.) also extended micturition intervals, but decreased the micturition pressure. These results indicate that AH-9700, (+)-pentazocine and DTG improve abnormal frequent urination caused by acetone-induced cystitis in a manner different from that of oxybutynin.