The effect of chronic morphine treatment on the I(A) (transient outward K+ current) of prefrontal cortical neurons of newborn rat. On this basis, we use AGS3 antibody to inhibit the function of AGS3, for observing the impact of AGS3 on the I(A), thus further explore the mechanism of AGS3 protein in morphine addiction.By using whole-cell patch-clamp technique, I(A) was recorded. In the whole-cell configuration, observed the impact of morphine on the current density-voltage curve (I-V) of I(A) and the effect of AGS3 antibody with three different concentrations on the I(A) of morphine treated rat prefrontal cortical neurons.Morphine increased the I(A). When the test potential was + 55 mV, different concentrations of AGS3, 10(-3) microg/L, 10(-2) micdrog/L and 10(-1) microg/L acted on morphine treated rat prefrontal cortical neurons, the enhanced IA by morphine was inhibited.Morphine increases the I(A), AGS3 protein may participate in signal transduction pathway involved with I(A).