运动和应激对海马5-羟色胺及其受体影响

Effects of exercise and stress on 5-HT and 5-HT1A receptor

目的通过观察体力运动和慢性应激对海马5-羟色胺(5-HT)水平及5-HT1A受体mRNA表达的影响,探讨运动减缓应激性海马损伤作用在海马5-HT系统水平的可能机制。方法将24只成年雄性Wistar大鼠随机分为对照组、运动组、应激组和运动+应激组。用高效液相-电化学检测法测定海马5-HT水平,实时-荧光定量PCR法检测海马5-HT1A受体mRNA的表达。结果与对照组比较,运动组海马5-HT水平显著升高(P<0.01),而应激组海马5-HT水平明显降低(P<0.01);与单纯应激组比较,运动+应激组5-HT水平略高于应激组,但差异无统计学意义(P>0.05)。运动组和应激组的5-HT1A受体mRNA相对表达量分别是对照组的(4.49±1.59),(0.22±0.06)倍,且与对照比较差异有统计学意义(P<0.01)。运动+应激组5-HT1A受体mRNA相对表达量是对照组的(0.87±1.22)倍,显著高于单纯应激组(P<0.05)。结论运动可能是通过提高海马5-HT水平和5-HT1A受体表达来改善海马5-HT系统功能,发挥减缓慢性应激性海马损伤的作用,而且5-HT1A受体表达的上调在此效应中作用更为明显。

Objective To investigate the mechanism of attenuating effect of physical exercise on chronic stress- induced hippocampal damages through observing different effects of exercise and stress on 5 - HT level and the mRNA expression level of 5 - HT1A receptor （5 - HT1A R）. Methods 24 adult male Wistar rats were randomly divided into four groups as follows： control group, exercise group, chronic stress group, exercise plus chronic stress group and 5 - HT levels were detected by high- performance liquid chromatography using electrochemical detection, and the expression levels of 5 - HTIAR mRNA were measured by real- time fluorescence quantitative reverse transcription polymerase chain reaction （RT - FQ - PCR）. Results Compared with the control group, 5 - HT levels in hippocampus increased significantly in the exercise group （ P 0.01）, decreased significantly in the chronic stress group（P〈 0.01）. Compared with the chronic stress group, 5 -HT levels were slightly higher than exercise stress group without statistecal significance（ P〉 0.05 ）. The relative expression levels of 5 - HT1AR mRNA in the exercise group and the chronic stress group are 4.49 ± 1.59 and 0.22 ± 0.06 times of those of the control group respectively with significant differences（ P〈 0.01 ）. The relative expression levels of 5 - HT1AR mRNA in the exercise stress group are 0.87± 1.22 times of those of the control group, significantly higher than those of the chronic stress group（ P 〈 0.05 ）. Conclusion Exercise attenuates chronic stress- induced hippocampal damages through improving the function of 5 - HT system in hippocampus. The up - expression of the 5 - HT1A R in hippocampus probably played a more important role.