G. Deley et L. Leybaert, EFFECT OF FLUNARIZINE AND METHYLPREDNISOLONE ON FUNCTIONAL RECOVERY AFTER EXPERIMENTAL SPINAL-INJURY, Journal of neurotrauma, 10(1), 1993, pp. 25-35
The effect of flunarizine and methylprednisolone on the recovery of so
matosensory evoked potentials (SEPs) was evaluated in an experimental
model of spinal cord impact injury in anesthetized cats. In addition,
the effect of flunarizine on posttraumatic spinal cord blood flow (SCB
F) (using the hydrogen clearance technique) and interstitial calcium a
nd potassium activity (ion-selective electrodes) was investigated. Aft
er the injury (600 g . cm), SEPs disappeared, followed by a spontaneou
s recovery to 17% of the preinjury amplitude at the end of the 4 h obs
ervation period. Flunarizine treatment (0.1 mg/kg IV, given 5 and 120
min after injury) resulted in a significantly improved recovery of SEP
s, reaching 52% of the preinjury amplitude. Methylprednisolone treatme
nt (30 mg/kg IV, given 5 min after injury) resulted in a 30% recovery
level, significantly better than in untreated animals but significantl
y inferior to flunarizine treatment. Combination of both treatments re
sulted in a 62% recovery level, significantly better than after methyl
prednisolone treatment alone. Flunarizine treatment had no significant
effect on the postinjury evolution of SCBF and interstitial potassium
activity; it did, however, significantly accelerate the recovery of i
nterstitial calcium activity, which sharply decreased immediately afte
r injury. It is concluded that intravenous administration of the calci
um entry blocker flunarizine improves the functional recovery of the s
pinal cord in the acute phase after experimental spinal impact injury.
The observed improvement is not achieved by an effect on local blood
flow but is possibly related to an inhibitory effect of the drug on ce
llular calcium entry.