S. Kuraoka, Huo Xuan, Yoshihiko Ito
2012
Citations
0
Influential Citations
0
Citations
Quality indicators
Journal
Neurourology and Urodynamics
Abstract
Hypothesis / aims of study Imidafenacin, a potent and selective antagonist of M1 and M3-muscarinic receptor subtypes, is now used clinically in Japan for the treatment of overactive bladder (OAB) [1-3]. Pharmacological studies of this agent showed selectivity in the bladder over salivary gland and brain. Oral administration of imidafenacin at low doses caused a more selective and longer-lasting binding to muscarinic receptors in the bladder than at other tissues such as the salivary gland, heart, colon, lung and brain, suggesting preferential muscarinic receptor binding in the bladder [2,3]. Pharmacokinetic data showed that the orally administered imidafenacin distributed at a higher concentration in the bladder than the serum or submaxillary gland of rats. The current study aimed to characterize further muscarinic receptor binding sites of currently synthesized [ 3 H]imidafenacin with high specific activity, in the rat bladder under the comparison with other tissues. Also, the muscarinic receptor binding of [ 3 H]imidafenacin in rat tissues was simultaneously compared with that of [N-methyl3 H] scopolamine methyl chloride ([ 3 H]NMS), a widely used selective radioligand of muscarinic receptors.