Tactile stimulation promotes the recovery of motor function in rats with cerebral ischaemia.

Abstract

Objectives: Tactile stimulation (TS) can promote neurogenesis and motor function recovery in rats with hypoxic-ischaemic brain injury, but the underlying mechanism is not clear. This study aimed to assess the effects of TS on neurological function in rats after cerebral ischaemia and explore the underlying mechanism.

Methods: Adult SD rats were randomly divided into a sham operation (SHAM) group, middle cerebral artery occlusion with tactile stimulation (TS-MCAO) group and middle cerebral artery occlusion with sedentary intervention (SED-MCAO) group. Twenty-four hours after MCAO, rats in the TS-MCAO group received TS for 20 min/d 5 d/w for 4 weeks. Cerebral blood flow (CBF), changes in body weight, behavioural scores, the infarct volume, corticospinal tract integrity, and neurochemical changes were measured, and Golgi-Cox staining, transmission electron microscopy and Western blotting were performed.

Results: CBF recovery was improved in the TS-MCAO group compared with the SED-MCAO group. Body weight and behavioural scores in the TS-MCAO group significantly changed after 28 days of intervention. After 14 and 28 days of intervention, the infarct volume decreased significantly, the ratios of fractional anisotropy increased and the ratios of apparent diffusion coefficient decreased, the ratios of Nacetylaspartate (NAA)/creatine (Cr) and glutamate (Glu)/ Cr increased. After 28 days of intervention, the complexity and density of dendrites, the number of synapses and the expression of synaptic plasticity-related proteins increased in the peri-infarct cortex.

Conclusion: TS can improve motor performance in rats with cerebral ischaemia and the improvement is correlated with synaptic plasticity. This finding would be helpful to provide a rehabilitation program for patients following stroke.