Description
InformationMirabegron (YM 178) is a selectiveβ3-adrenoceptoragonist withEC50of 22.4 nM.In vitroMirabegron concentration-dependently increases the accumulation of cAMP in CHO cells expressing human 3-adrenoceptors (ARs) with I.A. of 0.8. Mirabegron has little agonistic effect on 1- and 2-ARs. Mirabegron concentration-dependently relaxes rat and Human bladder smooth muscle strips precontracted with 10-6 M or 10-7 M carbachol with EC50 values of 5.1 µM and 0.78 µM, respectively. The maximal relaxant effects of Mirabegron are 94.0 % and 89.4% that of carbachol, respectively. Mirabegron is a time-dependent inhibitor of CYP2D6 in the presence of NADPH as the IC50 value in human liver microsomes decreased from 13 to 4.3 µM after 30 min preincubation. Mirabegron acts partly as an irreversible or quasi-irreversible metabolism-dependent inhibitor of CYP2D6.In vivoMirabegron produces a dose-dependent decrease in the frequency of rhythmic bladder contraction in anesthetized rats. 3 mg/kg i.v. Mirabegron suppresses the frequency to 2 counts/10 min. Mirabegron does not decrease the amplitude of rhythmic bladder contraction. Mirabegron decreases primary bladder afferent activity and bladder microcontractions in rats. Mirabegron (0.3 and 1 mg/kg) inhibits mechanosensitive single-unit afferent activities (SAAs) of Aδ fibers in response to bladder filling. SAAs of C-fibers decrease only at 1 mg/kg Mirabegron treatment. Mirabegron administration suppresses the mean bladder pressure and the number of microcontractions during an isovolumetric condition of the bladder. Mirabegron is efficient on facilitation of bladder storage. Mirabegron dose-dependently decreases the resting intravesical pressure. Mirabegron dose dependently decreases the frequency of nonvoiding contractions, considered an index of abnormal response in bladder storage. Mirabegron exhibits no significant effects on the amplitude of nonvoiding contractions, micturition pressure, threshold pressure, voided volume, residual volume, or bladder capacity.Cell Datacell lines:NCL-H2106, Colo699 and LNCAP cellsConcentrations:Incubation Time:Powder Purity:≥99%