Fig. 3.
Secretin facilitates GABAergic, but not glutamatergic, synaptic transmission in the rat cerebellum.A, Raw traces showing that evoked and spontaneous IPSCs were augmented by bath application of 30 nm of secretin. Paired stimuli (arrows), separated by a 50 msec interval, were given every 4 sec. Four overlaying traces are plotted in each case. B, Top traces on theleft, which were averaged from 50 evoked IPSCs, revealed that the amplitude and waveform of parallel fiber (PF)-PSC were unaffected by secretin, in sharp contrast to the evoked IPSC shown in the bottom trace. Mean data of the effect of 30 nm secretin on PF-PSCs and evoked IPSC are shown on theright. C, On the left, the normalized IPSCs from the cell shown in A andB revealed a reduction of paired-pulse ratio (IPSC2/IPSC1).Numbers in the parentheses denote the sample size. *p < 0.05 (paired ttest); ***p < 0.001 (t test).