Figure 6.

Spike-induced inhibition of evoked EPSCs in MSNs is mediated by muscarinic receptors. A, Traces from a representative experiment in which significant MSN EPSC suppression was induced by an LAI spike in control solution, for an interval of ∼30 ms (gray bars). In the presence of atropine, the baseline MSN EPSC amplitude was significantly increased, and a spike in the LAI no longer affected such EPSC. These effects were reversed on atropine washout. B, Average effects of application of atropine or methoctramine in 24 LAI–MSN pairs, in which significant spike-induced suppression of MSN EPSC was observed in control solution. The spike–EPSC interval was constant for each pair (range of 20–30 ms).