Abstract: Objective To explore the effect of aerobic exercise on behavioral function in rats with cerebral small vessel disease and its mechanism. Methods Eight-week-old male Sprague-Dawley rats were randomly divided into sham group (n = 16), model group (n = 16) and swimming group (n = 16). The model was developed with bilateral common carotid artery ligation. They were assessed with burrowing test after four weeks of swimming exercise. The levels of brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) protein in hippocampus were detected with Western blotting. The development of dendrites and synaptic spines in hippocampal neurons was observed with Golgi staining. The expression of Ki67, doublecortin (DCX) and Neun in hippocampal dentate gyrus was detected with immunofluorescence. Results Compared with the model group, the burrowing ability improved in the swimming group (P < 0.05), with increase of levels of BDNF and TrkB in hippocampus (P < 0.05), Ki67/DCX and Neun positive cells in hippocampal dentate gyrus (P < 0.05), and extension of dendrites and length of synaptic spine in hippocampal neurons (P < 0.05). Conclusion Aerobic exercise may promote the proliferation and differentiation of hippocampal neurons through BDNF/TrkB signaling pathway, expression of Ki67/DCX and Neun and development of hippocampal neurons, to improve behavioral function in rats with cerebral small vessel disease.

Key words: cerebral small vessel disease, aerobic exercise, hippocampus, behavioral function, brain-derived neurotrophic factor, tropomyosin receptor kinase B, rats