Abstract
The concentrations of the metabolites of propiverine hydrochloride (1-methyl-4-piperidyl diphenylpropoxyacetate hydrochloride, abbreviated as P-4) in rat tissues were determined after p.o. administrations. The major metabolites were found to be as follows; 4-piperidyl diphenylpropoxyacetate (DM-P-4), 1-methyl-4-piperidyl benzilate (Dpr-P-4) and 1-methyl-4-piperidyl diphenyl-(2 carboxy) ethoxyacetate (ω-COOH-P-4) in the liver, Dpt-p-4, DM-P-4 in the kidney, and DM-P-4, DPr-P-4 in the lung. The unchanged compound was also detected in the liver, kidney and lung. In all instances, the tissue concentrations were higher than those in the plasma. All pharmacologically active compounds such as the unchanged compound, 1-methyl-4-piperidyl benzilate N-oxide (DPr-P-4 (N→O)), Dpt-p-4 and 1-methyl-4-piperidyl diphenylpropoxyacetate N-oxide (P-4 (N→O)) were present in the urinary bladder, a target organ for P-4, at higher concentrations than in the plasma.