摘要
Objective:To investigate the expression of hippocampal synapse-related proteins including synaptophysin (SYN), postsynaptic density protein 95 (PSD95) and growth-associated protein 43 (GAP43) in rats with epilepsy accompanied by depression.Methods:The 3-month-old female clean grade SD rats were selected for the experiment.Lithium chloride pilocarpine was used to establish an epileptic rat model. Rats with successful epilepsy models were divided into epileptic depressive group (EWD group)and epileptic group with 10 in each group based on whether they were accompanied by depression. Furthermore, ten rats with matched body mass were taken as the depressive group and 10 were taken as control group. As for the depressive group rats, chronic unpredictable mild stress stimulation combined with orphanage was adopted to establish a model of depression.The depressive behaviors of rats were evaluated by body mass, sucrose preference test and open field test. Immunohistochemical staining and Western blot were used to detect the expression of SYN, PSD95 and GAP43 proteins in rat hippocampal tissue. SPSS 17.0 software was used for data statistical analysis, repeated measurement ANOVA was used for behavioral results, one-way ANOVA was used for inter group comparison of protein expression data, and LSD test was used for further pairwise comparison.Results:As for the body mass, there was significant interaction effect between the time and group among the 4 groups ( F=7.33, P<0.01). On the 8th day and the 29th day, the body weight of rats in the EWD group and the depressive group were lower than those in the epilepsy group (all P<0.05). The body weight of rats in the EWD group on the 29th day was lower than that on the first day ( P<0.05). As for the sucrose preference rates, there was significant interaction effect between the time and group among the 4 groups( F=2.67, P<0.05). The sucrose preference rate of EWD group on the15th and 29th day were lower than that on the first day (both P<0.05). The results of the open field test showed that the interaction effects of the number of vertical standing times( F=2.74) and the number of horizontal movement lattices ( F=1.76) both were not significant (both P>0.05), but both the time effect and group effect were significant (vertical standing times: Ftime=4.35, P<0.05, Fgroup=25.64, P<0.01; horizontal movement lattices: Ftime=12.75, P<0.01, Fgroup=21.37, P<0.01). The immunohistochemical results showed that there was a statistically significant difference in the number of positive cells expressing synaptic proteins SYN, PSD95 and GAP43 among the four groups of rats ( F=93.85, 58.66, 98.84, all P<0.05). The numbers of positive cells of SYN (11.73±4.30), PSD95 (24.47±7.58) and GAP43 (9.40±3.50) in the epilepsy group were lower than those in the control group ((51.00±15.39), (55.60±13.17) and (29.53±4.05)) (all P<0.05). The numbers of positive cells of SYN (5.80±3.53), PSD95 (12.87±4.03) and GAP43 (5.33±3.50) in the EWD group were lower than those in the depressive group ((11.33±3.22), (48.13±12.69) and (15.47±5.21) )(all P<0.05). Western blot results showed that there were statistically significant differences in the expression of synaptic proteins SYN, PSD95 and GAP43 among the four groups of rats ( F=13.19, 9.38, 16.80, all P<0.05). The expression levels of SYN, PSD95 and GAP43 in the epilepsy group were lower than those in the control group (all P<0.05). The expression levels of SYN, PSD95 and GAP43 in the EWD group were lower than those in the epilepsy group and the depressive group (all P<0.05). Conclusion:The low expression of SYN, PSD95 and GAP43 proteins in the hippocampus of rats with epilepsy accompanied by depression may be related to their pathogenesis.
摘要
OBJECTIVE@#To assess the value of Ploton silver staining and phalloidin-iFlour 488 staining in observation of the morphology of osteocyte dendrites of mice at different developmental stages.@*METHODS@#The humerus and femurs were harvested from mice at 0 (P0), 5 (P5), 15 (P15), 21 (P21), 28 (P28), and 35 days (P35) after birth to prepare cryo-sections and paraffin sections. HE staining of P35 mouse femur sections served as a reference for observing osteocytes in the trabecular bone and cortical bone. The humeral sections at different developmental stages were stained with Ploton silver staining to observe the morphology of osteocytes and canaliculi, and the canalicular lengths in the cortical and trabecular bones of the humerus of the mice in each developmental stage were recorded. The cryo-sections of the humerus from P10 and P15 mice were stained with phalloidin iFlour-488 to observe the morphology of osteocytes and measurement of the length of osteocyte dendrites in the cortical bone.@*RESULTS@#In the trabecular bone of the humerus of P0-P15 mice, Ploton silver staining only visualized the outline of the osteocytes, and the morphology of the canaliculi was poorly defined. In P21 or older mice, Ploton silver staining revealed the morphology of the trabecular bone osteocytes and the canaliculi, which were neatly arranged and whose lengths increased significantly with age (P21 @*CONCLUSIONS@#Mouse osteocyte dendrites elongate progressively and their arrangement gradually becomes regular with age. Ploton silver staining can clearly visualize the morphology of the osteocytes and the canaliculi in adult mice but not in mice in early stages of development. Phalloidin iFlour-488 staining for labeling the cytoskeleton can be applied for mouse osteocytes at all developmental stages and allows morphological observation of mouse osteocytes in early developmental stages.