Pharmacokinetics of mirodenafil and its two metabolites, SK3541 and SK3544, after intravenous and oral administration of mirodenafil to streptozotocin-induced diabetes mellitus rats

The area under the curve (AUC) of mirodenafil after intravenous administration in diabetes mellitus induced by streptozotocin (DMIS) rats was significantly smaller (by 28.0%) than the control value, and the AUC _SK3541/AUC_mirodenafil ratio was significantly greater (by 130%) in DMIS rats. This may be explained by the significantly faster hepatic CL_int of mirodenafil, owing to increased hepatic CYP1A, CYP2B1/2, CYP2D, and CYP3A expression, and a faster hepatic blood flow rate, compared with control values. The AUC of mirodenafil after oral administration was comparable between DMIS and control rats, possibly because of the comparable intestinal CL_int, which may be attributable to increased CYP1A2 expression and decreased CYP2D expression in the intestines of DMIS rats.