Reduce by 25% Examples of prespikes.
(A-B) Two examples of prespikes in simultaneous pre- and postsynaptic patch-clamp recordings. From top to bottom: calyx of Held AP, which was elicited by afferent stimulation, CC prespike, associated VC prespike. Recordings were made at room temperature in brainstem slices from 7–10 days old Wistar rats . Horizontal scale bar: 0.5 ms. Vertical (from top to bottom): 50 mV, 2 mV, 1 nA. Arrows indicate the amplitudes that were quantified in (C). (C) Relation between the amplitude of the positive peak of the prespike measured in CC and the amplitude of the first negative peak of the prespike measured in VC in the same cell. Slope of the fitted line is -4.6 mV/nA. (D). Six examples of CC prespikes from in vivo recordings of a target neuron of the calyx of Held in 3–5 days old Wistar rats . During this period the calyx of Held expands over the postsynaptic cell. Note the small upward deflection immediately preceding the EPSP in the bottom three prespikes (arrow heads) which, we will argue, arises from the presynaptic calcium current running through the synaptic cleft (see also Fig 5B). Scale bar indicates 0.5 mV and 0.5 ms.