Study on the molecular mechanism of beta3- adrenoceptor subtypes mediating rat detrusor relaxation / 解放军医学杂志

ABSTRACT

Objective To investigate the molecular mechanisms of beta3 adrenoceptor subtypes mediating rat detrusor relaxation. Methods Cyclic adenosine monophosphate(cAMP) was detected by radioimmunoassay, the effects of the cyclic AMP inhibitor SQ 22,536 and the cyclic AMP dependent protein kinase inhibitor H 89 on the relaxation elicited by ISO and BRL37344A in the rat ditrusor were investigated based on pharmacological evaluations. Results After the stimulating of ? AR by ISO, the levels of intracellular cAMP was increased, and the relaxation mediated via ISO could be partly inhibited by SQ 22,536 or H 89 The concentrations of intracellular cAMP had no changes in the presence of SQ 22,536 or H 89, and the relaxant responses to BRL37344A was not affected by SQ 22,536 or H 89. Conclusion The effects of ISO via? AR on relaxant responses to detrusor was mediated mainly by the cyclic AMP independent pathway and in part by the cyclic AMP dependent pathway, but cAMP PKA pathway were not involved in the beta3 adrenoceptor signaling pathway