ATP受容体刺激で発生した外向き電流応答の性質

Properties of the ATP-induced outward current response were investigated under voltage-clamp and compared with those of the adenosine (Ade)-induced outward current response in the folliculated oocyte of Xenopus laevis. The reversal potential of ATP- and Ade-induced responses corresponded with the equilibrium potential of K^+, suggesting the opening of K^+ channels produced these responses. Either glibenclamide or phentolamine significantly inhibited both responses, showing an involvement of K_ channels in these responses. The application of UTP selectivity depressed the Ade-induced response without affecting the response to ATP. These results suggested that the ATP response could be produced via an intrinsic ATP receptor but not Ade receptor