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Neurophysiology

, Volume 27, Issue 1, pp 19–23 | Cite as

Effects of dexamethasone on the electrical activity of spinal neurons in rats with the transected sciatic nerve

  • V. A. Chavushyan
  • L. A. Matinyan
  • A. S. Andreasyan
  • T. K. Kipriyan
Article

Abstract

Effects of the glucocorticoid hormone dexamethasone on the reflex discharges in the lumbar ventral roots and background activity (BA) of single neurons in the dorsal laminae of spinal grey were studied in rats after transection of the sciatic nerve. Administration of the hormone during early post-traumatic period (up to seven days) evoked no significant changes in the amplitude of increased (due to the postdenervation hyperreflexia) monosynaptic discharges on the side of nerve transection. At the same time, the monosynaptic discharges grew by 150–170% on the intact side. During later post-transection periods (up to 35 days), when ventral root reflex discharges were suppressed, dexamethasone facilitated reflex transmission via the polysynaptic segmental pathways on both the operated and intact sides. Nonetheless, the monosynaptic component of reflex discharges on the injured side did not recover. Dexamethasone treatment resulted in an increase in the number of BA-generating interneurons within the superficial dorsal horn laminae, and in a decrease in the proportion of units generating bursting activity (possibly of pathological nature).

Keywords

Dexamethasone Sciatic Nerve Dorsal Horn Spinal Neuron Ventral Root 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Publishing Corporation 1996

Authors and Affiliations

  • V. A. Chavushyan
    • 1
  • L. A. Matinyan
    • 1
  • A. S. Andreasyan
    • 2
  • T. K. Kipriyan
    • 2
  1. 1.Orbeli Institute of PhysiologyNational Academy of Sciences of ArmeniaYerevanArmenia
  2. 2.Institute of Applied Problems of PhysicsNational Academy of Sciences of ArmeniaYerevanArmenia

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