Early locomotor training with clonidine in spinal cats.
Connie Chau, Hugues Barbeau, Serge Rossignol.
Centre de Recherche en Sciences Neurologiques, Facult‚ de M‚decine,
Universit‚ de Montr‚al, School of Physical and Occupational therapy, McGill
University, Montr‚al.
APStracts 4:0251N, 1997.
ABSTRACT
Clonidine, a noradrenergic alpha-2 agonist, can initiate locomotion early
after spinalisation in cats. Since this effect lasts 4-6 hours, we have
injected clonidine daily, intraperitoneally or intrathecally, and intensively
trained 5 spinal cats to perform hindlimb walking on a treadmill starting at
day 3 and continuing until 10 days post-transection. Each day, clonidine was
injected to induce locomotor activity and cats were trained to walk with as
much weight support as possible and at different speeds during multiple (1-5)
locomotor training sessions, each lasting from 10 to 20 minutes, until the
effects of clonidine wore off. Electromyographic (EMG) activity synchronized
to video images of the hindlimbs were recorded before and after each clonidine
injection. The results showed, firstly, a day to day change of the locomotor
pattern induced by clonidine from the 3rd to the 11th day including an
increase in the duration of the step cycle, an increase in the duration of
extensor EMG activity, and an increase in total angular excursion of the hip,
knee and ankle joints. Secondly, after 6-11 days of this regimen, there was an
emergence of a coordinated locomotor pattern with weight support of the
hindquarters that was visible even before that day's clonidine injection. The
results suggested that daily injection of clonidine followed by early and
daily interactive locomotor training can enhance the recovery of locomotion in
spinal cats.
Received 24 January 1997; accepted in final form 9 September 1997.
APS Manuscript Number J71-7.
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 7 October 1997