Constraint-induced movement therapy promotes motor function recovery and downregulates phosphorylated extracellular regulated protein kinase expression in ischemic brain tissue of rats

Abstract

Motor function impairment is a common outcome of stroke. Constraint-induced movement therapy (CIMT) involving intensive use of the impaired limb while restraining the unaffected limb is widely used to overcome the effects of ′learned non-use′ and improve limb function after stroke. However, the underlying mechanism of CIMT remains unclear. In the present study, rats were randomly divided into a middle cerebral artery occlusion (model) group, a CIMT + model (CIMT) group, or a sham group. Restriction of the affected limb by plaster cast was performed in the CIMT and sham groups. Compared with the model group, CIMT significantly improved the forelimb functional performance in rats. By western blot assay, the expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi of cerebral ischemic rats in the CIMT group was significantly lower than that in the model group, and was similar to sham group levels. These data suggest that functional recovery after CIMT may be related to decreased expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi.

Keywords

• nerve regeneration; constraint-induced movement therapy; mitogen-activated protein kinase signaling system; brain ischemia; locomotion; recovery; cortex; hippocampus; middle cerebral artery occlusion; foot fault test; balance beam walking; rats; NSFC grants; neural regeneration