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Updated: Jun 5, 2026

In Vivo Intracellular Recording of Type-Identified Rat Spinal Motoneurons During Trans-Spinal Direct Current Stimulation
Published on: May 11, 2020
Modulation of afterhyperpolarization evoked by doublets and increasing number of stimuli in rat motoneurons
Włodzimierz Mrowczynski1, Piotr Krutki, Vihren Chakarov
1Department of Neurobiology, University School of Physical Education, Poznań, Poland. mrowczynski@awf.poznan.pl
Abstract:
The authors studied the influence of variable stimulation patterns on parameters of afterhyperpolarization (AHP) in rat spinal motoneurons using intracellular recording of antidromic action potentials. The action potentials analyzed were evoked by either (a) a single stimulus or pair of stimuli with gradually increasing interpulse intervals (IPI) of 5-20 ms or (b) an increasing number of stimulus pulses, from 1 to 4, at a constant IPI. It was demonstrated that modulations of AHP parameters after 2 pulses depended on the IPI, whereas the most significant changes in these parameters were found after the application of 2 or 3 stimuli in a series. The authors propose that changes in the AHP parameters have functional significance for motoneuronal firing pattern and therefore for motor unit force development during tetanic contractions.
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