Abstract:ObjectiveTo observe synaptic protein expressions in the brain of permanent middle cerebral artery occlusion (pMCAO) model rats on 2 and 7 after ischemic attack. Methods To establish a rat model of pMCAO. The rats with ischemia were randomly divided into 2-day group and 7-day group, taking rats with no occlusion as the sham group. On d 2 and d 7 post-operation, pathological changes in ischemic brain tissue were observed with H&E staining, and expression of synapsin-I, postsynaptic density protein 95 (PSD-95), α-synuclein were examined with immunohistochemical staining. ResultsCompared with the sham group, there were a large amount of neurons lost, and degeneration and necrosis of scattered neurons in the brain tissue in the model group. On the 2nd day post-ischemia, in the model group, expressions of synapsin-I in the CA1 and CA3 regions and cortex were significantly reduced (P<0.05 or P<0.01), PSD-95 in CA1 region and cortex was significantly reduced (P<0.05 or P<0.01), while α-synuclein in CA1 region significantly accumulated (P<0.01). On the 7th day after ischemia, in the model group expression of synapsin-I in CA1 region and cortex were still significantly reduced (P<0.01), PSD-95 in CA1 region and cortex also significantly reduced (P<0.05 or P<0.01), and α-synuclein in CA1, CA3 regions and cortex was significantly increased (P<0.05 or P<0.01). ConclusionsIn the brain tissue of pMCAO model rats, expression of synaptic proteins is significantly changed and varies along with the time-course of ischemia, probably, it might be related to synapse remodeling. The expression of synapse-associated proteins is closely related to the degree of ischemic injury.