Miniature EPSC (mEPSC) analysis indicates post- rather than pre-synaptic effects of CGRP. A, Original current traces of mEPSC recorded in an individual SG neuron in the presence of TTX (1 μM) show that CGRP (10 nM; 10 min) increases amplitude but not frequency of mEPSCs. B, C: Normalized cumulative distribution analysis of mEPSC amplitude and frequency in the same neuron as in 5A shows that CGRP caused a significant shift toward higher amplitude (B, P < 0.001, Kolmogorov-Smirnov test) but had no effect on the interevent interval (frequency) distribution (C). In the sample of neurons (n = 5) CGRP selectively increased mean mEPSC amplitude (P < 0.05, paired t-test) but not mEPSC frequency (see bar histograms in B, C). Symbols and error bars represent mean ± SEM. Neurons were recorded in voltage-clamp at -60 mV. * P < 0.05.
Bird et al. Molecular Pain 2006 2:31 doi:10.1186/1744-8069-2-31