Search results for "Sphincter tone"

Relaxation by β3-adrenoceptor agonists of the isolated human internal anal sphincter

2009

In this study, responses of beta(3)-adrenoceptor agonists were examined on human isolated internal anal sphincter (IAS) in order to explore their relaxant effects on hypertonicity of IAS.The relaxant efficacy (E(max)) and potency (-logIC(50)) of BRL37344 and SR58611A, beta(3)-adrenoceptor agonists, were examined in contracted IAS muscle strips. The presence of beta(3)-adrenoceptors, and changes in intracellular calcium and cyclic nucleotide levels in IAS muscle were tested by Western blotting, epifluorescence microscopy and enzyme immunoassay, respectively.BRL37344 and SR58611A relaxed contracted IAS muscle (E(max)=27+/-3% and 35+/-3%; -logIC(50)=6.26+/-0.24 and 4.87+/-0.13; respectively). …