Locomotor recovery in the chronic spinal rat: effects of long-term treatment with a 5-HT2 agonist

Eur J Neurosci. 2002 Aug;16(3):467-76. doi: 10.1046/j.1460-9568.2002.02088.x.

Abstract

A complete transection of the spinal cord at a low thoracic level induces a paraplegic syndrome that is accompanied by a loss of spinal cord serotonin content. Former experimental data suggest that the central pattern generator for locomotion, located in the lumbar segments of the spinal cord, might be able to generate rhythmic motor outputs (similar to automatic walking under certain circumstances) involving exteroceptive stimulations and activation of serotonergic receptors. In the present study, we investigated the effects of a chronic treatment using a serotonergic agonist, delivered continuously to the sublesionned spinal cord, and its effect on motor function recovery. The data obtained from behavioural, kinematic and electromyographic measurements suggest that the chronic stimulation of 5-HT2 type receptors allows motor function recovery. Behavioural measurements show a clear improvement in motor performances when compared to spinal animals (confirmed by kinematic observations): alternating steps and foot placement is recovered in these animals. However, electromyographic data demonstrate that the pattern of activation of the muscles is only restored partially.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Drug Administration Schedule
  • Electromyography
  • Female
  • Hindlimb / innervation
  • Hindlimb / physiology
  • Locomotion / drug effects*
  • Locomotion / physiology
  • Muscle Contraction / drug effects
  • Muscle Contraction / physiology
  • Muscle, Skeletal / innervation
  • Muscle, Skeletal / physiology
  • Nerve Net / drug effects*
  • Nerve Net / metabolism
  • Nerve Net / physiopathology
  • Neurons / drug effects*
  • Neurons / metabolism
  • Periodicity
  • Quipazine / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Serotonin / drug effects*
  • Receptors, Serotonin / metabolism
  • Recovery of Function / drug effects
  • Recovery of Function / physiology
  • Serotonin Receptor Agonists / pharmacology*
  • Spinal Cord / drug effects*
  • Spinal Cord / metabolism
  • Spinal Cord / physiopathology
  • Spinal Cord Injuries / drug therapy*
  • Spinal Cord Injuries / metabolism
  • Spinal Cord Injuries / physiopathology
  • Treatment Outcome
  • Video Recording

Substances

  • Receptors, Serotonin
  • Serotonin Receptor Agonists
  • Quipazine