Potential of dorsal surface on stimulation of cat’s leg skin cover


  • O. O. Shugurov Oles Honchar Dnipropetrovsk National University

Abstract

Under experimental conditions the changes of cord dorsum potentials (CDP) of a spinal cord (SC) of cats were explored. Mechanical activation of the skin (S) and peripheral nerves (N) was made separately or simultaneously. The activation leads to a skin generated potential (S-CDP), which parameters correspond to second negative (N2) component of N-CDP. The activation of a major hair in the skin produces potential confirming an N1-component of N-CDP. The amplitude of all components of S-CDP is less than of all components of N-CDP. Shift of an activation point of the skin upwards reduces a stage of latency and duration of S‑CDP, however voltage of this potential is enlarged. The initial activation of a nerve carries out a long-time (up to 3 sec) decrease of S-CDP. It is testifies to antidromic influence of depolarization of primary afferents on dermal receptors. Our data sustain a principle of somatotopic representation of dermal zones in SC.

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Published
2006-02-15
Section
Articles