Noronha-Blob_1990_Life.Sci_46_1223

The potency and selectivity of (-)cis-2,3-dihydro-3-(4-methylpiperazinylmethyl)-2-phenyl-1,5 benzothiazepin-4-(5H)one HCl (BTM-1086) for muscarinic receptor subtypes was compared in functional assay systems, in guinea pig peripheral tissues, to known reference drugs: atropine (nonselective), pirenzepine (M1), AF-DX 116 (M2) and HHSiD (M3). Like atropine, BTM-1086 was a potent, nonselective, competitive muscarinic antagonist with no detectable antispasmodic activity in urinary bladder or ileal muscle. In vivo, in the guinea pig cystometrogram, BTM-1086 depressed intravesical bladder pressure (PvesP) with the same efficacy and potency as oxybutynin, a drug used clinically for the treatment of urinary incontinence. The pharmacological profile of BTM-1086, however, suggests that it may not be suitable for development for bladder dysfunction disorders.