Figure 5. Large amplitude events are climbing fiber (CF) EPSPs mediated by AMPARs.

(A) Mean peak amplitude of large amplitude events as a function of the holding potential. Inset: Expanded trace of a single large amplitude event to illustrate the slow kinetics and large amplitude. Inset x-axis: 400 ms; y-axis: 47 mV. (B) Mean inter-event interval as a function of holding potential. Error bars indicate standard error of mean in A and B (N = 5 cells). (C) Representative trace of a Purkinje neuron recorded in voltage clamp mode at −65 mV before and after application of CNQX. (D) Current-voltage relation of CF EPSCs (N = 3 cells). (E) Representative trace showing all-or-none EPSCs upon stimulation of CFs in the presence of APV and Gabazine (top trace; N = 7 cells). Stimulation at 500 μA resulted in either transmission failure (flat line) or EPSCs of similar amplitudes. In the same cell, all-or-none EPSCs were abolished by the addition of CNQX (bottom trace; N = 5 cells). Grey arrowhead shows stimulus artifact.

DOI: http://dx.doi.org/10.7554/eLife.09158.011

Figure 5—figure supplement 1. Large amplitude events do not require activation of NMDA receptors.

Representative trace of a Purkinje neuron recorded in voltage clamp mode at −65 mV in the absence (top trace) and presence of APV (N = 5 cells).

DOI: http://dx.doi.org/10.7554/eLife.09158.012

Figure 5—figure supplement 2. CF and PF glutamatergic synaptic inputs are clearly distinguishable.

(A) Representative trace from one cell held at −65 mV showing large amplitude (blue arrowheads) and small amplitude (green arrowheads) EPSCs. (B) Box plot showing distribution of peak amplitudes of large amplitude, CF and small amplitude parallel fiber (PF) EPSCs. Solid black line indicates median values and shaded grey boxes show inter-quartile ranges. (C) Coeffecient of variation (CV) of peak amplitudes of CF and PF EPSCs (N = 6 cells).

DOI: http://dx.doi.org/10.7554/eLife.09158.013