Figure 5

Sumatriptan inhibits evoked IPSCs in PAG neurons. (A) Time course of evoked IPSC amplitude (eIPSC Ampl) during application of sumatriptan (3 μM). (B) Averaged evoked IPSCs before (control), during application of sumatriptan (3 μM) and following washout (wash). (C) Averaged evoked IPSCs in response to identical paired stimuli (IPSC1-2 interval = 70 ms) for the traces in B, with IPSC₁ normalized to demonstrate relative facilitation of IPSC₂ during superfusion of sumatriptan (3 μM). (D) Concentration-response curve of the reduction in evoked IPSC amplitude produced by sumatriptan, expressed as a percentage of the pre-sumatriptan level, with a logistic function fitted to determine the IC₅₀. (E) Bar chart showing the evoked IPSC amplitude in the presence of sumatriptan (1 μM), expressed as a percentage of the pre- sumatriptan level, in neurons which received no prior treatment (control) and those which were pre-incubated in BRL15572 (10 μM) and/or NAS181 (10 μM). In (E) *, ** denote p < 0.05, 0.01. Traces in (A – C) are from the same neuron.