Axonal plasticity is associated with motor recovery following amphetamine treatment combined with rehabilitation after brain injury in the adult rat.
Clinical and laboratory studies have suggested that amphetamine treatment when paired with rehabilitation results in improved recovery of function after stroke or traumatic brain injury. In the present study, we investigated whether new anatomical pathways developed in association with improved motor function after brain damage and amphetamine treatment linked with rehabilitation. Following a unilateral sensorimotor cortex lesion in the adult rat, amphetamine (2 mg/kg) was administered in conjunction with physiotherapy sessions on postoperative days two and five. Physiotherapy was continued twice daily for the first 3 weeks after injury, and then once daily until week six. Performance on skilled forelimb reaching and ladder rung walking was used to assess motor improvement. Our results show that animals with sensorimotor cortical lesions receiving amphetamine treatment linked with rehabilitation had significant improvement in both tasks. Neuroanatomical tracing of efferent pathways from the opposite, non-damaged cortex resulted in the novel finding that amphetamine treatment linked with rehabilitation, significantly increased axonal growth in the deafferented basilar pontine nuclei. These results support the notion that pharmacological interventions paired with rehabilitation can enhance neuronal plasticity and thereby improve functional recovery after CNS injury.
Ramic
Maya
M
Neuroscience Program, Neurobiology and Anatomy Loyola University Medical Center, Maywood, IL 50153, USA.
Emerick
April J
AJ
Bollnow
Melanie R
MR
O'Brien
Timothy E
TE
Tsai
Shih-Yen
SY
Kartje
Gwendolyn L
GL
D000661:Amphetamine / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D001369:Axons / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D001710:Biotin / Q000031:analogs & derivatives; D001930:Brain Injuries / Q000188:drug therapy* / Q000503:physiopathology / Q000534:rehabilitation*; D000697:Central Nervous System Stimulants / Q000494:pharmacology / Q000627:therapeutic use; D003911:Dextrans; D004195:Disease Models, Animal; D004525:Efferent Pathways / Q000187:drug effects / Q000502:physiology; D020439:Growth Cones / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D008297:Male; D009044:Motor Cortex / Q000187:drug effects* / Q000293:injuries / Q000503:physiopathology; D009416:Nerve Regeneration / Q000187:drug effects / Q000502:physiology; D009473:Neuronal Plasticity / Q000187:drug effects* / Q000502:physiology; D010291:Paresis / Q000188:drug therapy / Q000503:physiopathology / Q000534:rehabilitation; D026741:Physical Therapy Modalities; D011712:Pyramidal Tracts / Q000187:drug effects / Q000502:physiology; D051381:Rats; D020318:Rats, Long-Evans; D020127:Recovery of Function / Q000187:drug effects* / Q000502:physiology; D016896:Treatment Outcome
D000697:Central Nervous System Stimulants; D003911:Dextrans; C076397:biotinylated dextran amine; D001710:Biotin; D000661:Amphetamine