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Fig. 4. Effect of ovotestis (OT) mechanical stimulation on the frequency of
afferent spikes in the intestinal nerve. (A) Representative traces from three
electrodes placed on the intact nerve (see
Fig. 1). A wooden applicator
stick mounted on a micro manipulator was used to gently stroke the surface of
the OT for 3 s; arrow indicates the onset of stimulation. (B) A representative
portion of the record from A is amplified to illustrate the discrimination of
efferent spikes (open arrowheads) and afferent spikes (filled arrowheads)
based on inter-spike intervals recorded at distal and proximal electrodes
positioned along the seminal vesicle; signals recorded at the central
electrode were not used for this purpose. (C) Raster plot showing the timing
of afferent spike activity for 30 s periods before and after the stimulus. The
arrow at time 0 indicates the onset of mechanical stimulation.