Decreased contractile response after exposure of the rat aorta to Db cAMP or IBMX.

ABSTRACT

Isometric tension developed by different receptor agonists was found to be decreased after pretreatment of rat aortic rings with IBMX or Db cAMP and only partially restored by CaCl2 and A 23187. The contraction produced by Bay k 8644 was converted into dose-dependent relaxation after pretreatment of the aorta rings with Db cAMP or IBMX. An alteration of the calcium channel is assumed to play a common role in the cAMP-dependent inhibition of the smooth muscle contraction.