Effects of exercise on depressive-like behavior and synaptic transmission in hippocampal dentate gyrus granule cells in depression model mice
10.3760/cma.j.cn371468-20240319-00122
- VernacularTitle:运动对抑郁模型小鼠抑郁样行为及海马齿状回颗粒细胞突触传递的作用
- Author:
Yuping XIA
1
;
Chuan'an ZHU
;
Zengming MA
;
Jindong CHEN
Author Information
1. 福建医科大学临床医学部，福州 350122
- Keywords:
Exercise;
Hippocampus;
Granule cells;
Excitation/inhibition ratio;
Synaptic transmission;
Whole-cell recording;
Mouse
- From:
Chinese Journal of Behavioral Medicine and Brain Science
2024;33(7):590-596
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the changes in synaptic transmission function of hippocampal dentate gyrus granule cells in depression model mice induced by chronic unpredictable mild stress (CUMS) and to explore the effect of exercise on it.Methods:Totally 48 SPF grade 7-week-old male C57BL/6J mice were randomly compartmentalised into control group (CTRL group), model group (CUMS group), model + exercise group (CUMS+ EXE group), and model + fluoxetine group (CUMS+ FLX group), with 12 mice in each group. CUMS method was used for preparating the depression model for 21 d. Mice in the CUMS+ EXE group were given roller locomotion training and mice in the CUMS+ FLX group were given fluoxetine intraperitoneally (10 mg/kg) daily during the modelling period, and the other two groups were administrated intraperitoneally with equal volume of 0.9% NaCl solution.Sucrose preference test (SPT), tail suspension test (TST) and forced swimming test (FST) were used to detect depressive-like behavior, and open field test (OFT) was used to detect anxiety-like behavior. Whole-cell recordings were used to detect spontaneous excitatory postsynaptic currents (sEPSC), spontaneous inhibitory postsynaptic currents (sIPSC), miniature excitatory postsynaptic currents (mEPSC), and miniature inhibitory postsynaptic currents (mIPSC) in hippocampal dentate gyrus granule cells.One-way ANONA was performed to analyze the data by SPSS 23.0.Results:(1) There were statistically significant differences among the 4 groups of mice in terms of activity time in the center, total distance of OFT and sugar preference rate( F=37.85, 18.41, 28.81 all P<0.01). The activity time in the center((47.81±3.51)s) and total distance((19.63±1.24)m) of OFT and sugar preference rate((55.63±9.11)%) in the CUMS group were lower than those in the CTRL group (all P<0.01), while those in the CUMS+ EXE group((59.87±3.25)s, (23.18±1.24)m, (69.03±8.22)% respectively) were higher than those in the CUMS group (all P<0.05).The sugar preference rate of the CUMS+ EXE group was lower than that in the CTRL group and CTRL+ FLX group (both P<0.01). The differences in immobility time of TST and FST were statistically significant among the 4 groups of mice ( F=113.70, 56.97, both P<0.01). The immobility time of TST and FST of the CUMS group was lower than that of mice in the CTRL group (both P<0.01), while that in the CUMS+ EXE group were lower than that in the CUMS group (both P<0.05) and higher than that in the CTRL group (both P<0.01). (2)There were statistically significant differences in frequency, amplitude and quantification of sEPSC among the 4 groups of mice ( F=22.02, 17.98, 179.00, all P<0.01). The sEPSC frequency, amplitude, and quantification of mice in the CUMS group were lower than those in the CTRL group (all P<0.05), while those in the CUMS+ EXE group were higher than those in the CUMS group (all P<0.05) and lower than those in the CTRL group and CUMS+ FLX group (all P<0.05). The differences in frequency and quantification of sIPSC among the 4 groups of mice were statistically significant ( F=22.12, 184.80, both P<0.01). The sIPSC frequency and quantification of mice in the CUMS group were higher than those in the CTRL group (both P<0.05), while those in the CUMS+ EXE group were lower than those in the CUMS group (both P<0.05) and higher than those in the CTRL group (all P<0.05).The difference in quantification of sEPSC/sIPSC ratios among the 4 groups of mice was statistically significant ( F=267.10, P<0.01). The quantification of sEPSC/sIPSC ratio of mice in the CUMS group was lower than that in the CTRL group ( P<0.05). The quantification of sEPSC/sIPSC ratio of mice in the CUMS+ EXE group was higher than that in the CUMS group ( P<0.05) and lower than that in the CTRL group and CUMS+ FLX group(both P<0.05). (3) The differences in mEPSC frequency and amplitude among the 4 groups of mice were statistically significant ( F=25.07, 23.57, both P<0.01). The mEPSC frequency and amplitude in the CUMS group were lower than those in the CTRL group (both P<0.05), while those in the CUMS+ EXE group were higher than those in the CUMS group (both P<0.05) and lower than those in the CTRL group and CUMS+ FLX group(all P<0.05). The difference in mIPSC frequency among the 4 groups of mice was statistically significant ( F=13.79, P<0.01). The mIPSC frequency of mice in the CUMS+ EXE group was lower than that in the CUMS group ( P<0.05) and higher than that in the CTRL group ( P<0.05). Conclusion:Exercise can partially improve depressive-like behaviours and enhances hippocampus granule cell synaptic transmission in depression model mice.
