Mg. Boyeson et al., COMPARATIVE EFFECTS OF FLUOXETINE, AMITRIPTYLINE AND SEROTONIN ON FUNCTIONAL MOTOR RECOVERY AFTER SENSORIMOTOR CORTEX INJURY, American journal of physical medicine & rehabilitation, 73(2), 1994, pp. 76-83
A recent investigation of the effects of the antidepressants desiprami
ne and trazodone on behavioral recovery in brain-injured animals sugge
sted that antidepressants, which act to increase noradrenergic activit
y in the brain, may facilitate the rate of recovery, whereas those tha
t act to increase serotonergic (5-HT) activity may hinder recovery and
reinstate deficits in recovered animals. The present study was design
ed to evaluate these findings further by assessing the effect of a sin
gle intraperitoneal injection of fluoxetine (a relatively pure 5-HT re
uptake blocker), amitriptyline (a mixed 5-HT and noradreneregic reupta
ke blocker with alpha1-adrenergic receptor blocking activity) or a sin
gle intraventricular infusion of 5-HT on recovery of beam-walking abil
ity in animals with a unilateral sensorimotor cortex injury. None of t
he drugs significantly affected the rate of recovery. Although fluoxet
ine was ineffective in reinstating the motor deficit in recovered anim
als, amitriptyline reinstated the deficit in a dose-dependent fashion.
Infusion of 5-HT resulted in an extremely transient reinstatement of
the deficit, which was largely attributable to its short-term sedative
properties. These results suggest that 5-HT may be less involved in f
unctional recovery than previously thought. They also add further supp
ort to previous findings that indicate that drugs which act to antagon
ize alpha1-adrenergic activity (e.g., phenoxybenzamine) may interfere
with motor recovery after sensorimotor cortex injury. An appreciation
of the potential impact of certain antidepressants on functional recov
ery in brain-injured patients appears warranted.