Fig. 6.

OFQ inhibits the L-type of VGCCs.A, The time course of the effect of orphanin FQ (OFQ; 1 μm) is shown in the absence and presence of nifedipine applied for the times indicated by thebars. The whole-cell currents were evoked at 5 sec intervals by 50 msec voltage steps to 0 mV from a holding potential of −80 mV. B, Superimposed current traces obtained by the protocol shown on top in the absence and presence of Bay K 8644 (Bay K; 1 μm) and the combined presence of Bay K 8644 and OFQ. Bay K 8644 introduced a slow component to the tail currents that was inhibited by OFQ.