Fig. 4.

The selective induction of LTS in μOR-positive FS GABAergic neurons of the vlPAG. The addition of drugs is indicated on top of each trace. (A and B) Wild-type FS GABAergic neurons. The LTS-positive GABAergic neurons expressed DAMGO-induced outward currents (A); none of the LTS-negative neurons showed a response to DAMGO (B). (C and D) α1G^−/− FS GABAergic neurons, both without LTS. The frequency of DAMGO-responding (C) and -nonresponding (D) neurons among α1G^−/− FS GABAergic neurons was similar to that in the wild-type. Vh, −50 mV.