Figure 2. Oxytocin induces VR rhythmic activity.

The application of 100(gray bar) depolarizes bilateral VRs at L2 and L5 levels (A). The early phase of VR depolarization is associated with bursts synchronous among all roots, followed by a partial repolarization. B, the rhythmic activity evoked by oxytocin on the four VRs shown in A (gray bar) is displayed, on a faster time scale, to depict synchronous bursts composed of apparently unrelated, fast intraburst oscillations. Histogram (C) illustrates, for each spinal cord, the average depolarization (recorded from 4 VRs) induced by oxytocin 100 nM, while the gray bar shows the mean value of all experiments. All vertical bars are 200 μV.