Vasopressin Inhibits Sarcolemmal ATP-Sensitive K+ Channels via V_1 Receptors Activation in the Guinea Pig Heart

概要

論文の詳細を見る
To examine the effect of vasopressin on the sarcolemmal ATP-sensitive K (K_<ATP>) channel, cell-attached, inside-out and open-cell-attached methods of patch clamp techniques were used in isolated guinea pig ventricular myocytes. Suppressing both glycolytic and oxidative ATP production attained K_<ATP> channel activation. In the cell-attached mode, vasopressin inhibited K_<ATP> channels in a concentration-dependent manner with an IC_<50> of 15.1±1.8nmol/L. In the inside-out configuration, vasopressin failed to block K_<ATP> channels. In the cell-attached mode, manning compound (1μmol/L), a V_1 receptor-selective antagonist, blocked the inhibitory action of vasopressin, although OPC-31260 (1μmol/L), a V_2 receptor-selective antagonist could not affect the action of vasopressin. In addition, vasopressin lost its inhibitory action on K_<ATP> channels when the channel was activated by pinacidil, a K channel opener and in the open-cell-attached mode effected by streptolysin-O. Thus, the inhibitory action of vasopressin K_<ATP> channels may occur via V_1 receptor related mechanism.
社団法人日本循環器学会の論文
2002-02-20