The effects of repeated rehabilitation "tune-ups" on functional recovery after focal ischemia in rats.
BACKGROUND
For most stroke survivors, rehabilitation therapy is the only treatment option available. The beneficial effects of early rehabilitation on neuroplasticity and functional recovery have been modeled in experimental stroke using a combination of enriched environment and rehabilitation. However, the impact of a secondary intervention, such as a periodic return to therapy, remains unclear.


OBJECTIVE
This study examines whether a return to enriched rehabilitation (ie, "tune-up") can further promote functional recovery or produce beneficial changes in brain plasticity in the chronic phase of stroke recovery.


METHODS
Rats were exposed to focal ischemia (endothelin-1 applied to forelimb sensorimotor cortex and dorsolateral striatum) and allowed to recover either in standard housing or in a combination of enriched environment and rehabilitative reaching for 9 weeks. Animals were then exposed to rotating periods of standard housing (5 weeks) and intensive "tune-up" therapy consisting of various sensorimotor/cognitive activities (2 weeks). Functional recovery was assessed using the Montoya staircase, beam-traversing, and cylinder tests, and Golgi-Cox analysis was used to examine dendritic complexity in the contralesional forelimb motor cortex.


RESULTS
Although early enriched rehabilitation significantly improved sensorimotor function in both the beam and staircase tests, "tune-up" therapy had no effect on recovery. Golgi-Cox analysis revealed no effect of treatment on dendritic complexity.


CONCLUSIONS
This study reaffirms the benefits of early rehabilitation for functional recovery after stroke. However, "tune-up" therapy provided no benefit in ischemic animals regardless of earlier rehabilitation experience. It is possible that alternative approaches in the chronic phase may prove more effective.
Clarke
Jared
J
BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St John's, Newfoundland, Canada.
Mala
Hana
H
Windle
Victoria
V
Chernenko
Garry
G
Corbett
Dale
D
D000704:Analysis of Variance; D000818:Animals; D002545:Brain Ischemia / Q000473:pathology / Q000534:rehabilitation*; D003712:Dendrites / Q000473:pathology; D049229:Dendritic Spines / Q000473:pathology; D004777:Environment; D006799:Housing, Animal; D008297:Male; D009043:Motor Activity; D009044:Motor Cortex / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function; D012046:Rehabilitation / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome