【摘要】 目的 探讨慢性不可预知轻度刺激(CUMS)大鼠模型中枢5-羟色胺(5-HT)含量、和色氨酸羟化酶-2(TPH-2)的表达变化以及抗抑郁药的影响。方法 24只大鼠被随机分成3组,每组8只,A组为对照组,不给予刺激;B组为刺激不给药组,即CUMS应激鼠;C组为刺激给药组,即CUMS应激+西酞普兰治疗组。实验为期6周,每周为大鼠称重,每3周测大鼠的糖水偏爱性,造模前后通过旷场试验评价大鼠行为,6周后对大鼠进行处死。处死后脑组织取样测定各脑区5-HT浓度及TPH-2 mRNA的表达水平。结果 经过6周干预,与A组比较,B组和C组体重明显降低(P<0.05);与A组及C组比较,B组糖水偏爱度显著降低(P<0.05),同时行为增多;B组5-HT浓度在海马中高于A组和C组,差异有统计学意义(P<0.05);在纹状体中,B组和C组5-HT浓度低于A组,差异有统计学意义(P<0.05);B组大鼠TPH2 mRNA在中缝核中表达低于A组,差异有统计学意义(P<0.05)。结论 慢性应激可能引起中枢海马5-HT浓度增高及中缝核TPH-2表达降低,抗抑郁药可能引起中枢海马5-HT浓度降低,但未能影响中枢TPH-2的表达。更多还原

【Abstract】 Objective To investigate the expression of TPH-2 and the content of 5-HT in different areas of the brain in rats with chronic unpredictable mild stress(CUMS),and explore the effects of antidepressant on expression of TPH-2 and content of 5- HT.Methods Twenty-four male SD rats were randomly assigned to control group(group A),CUMS group(group B),and CUMS + citalpram group(group C) with 8 rats in each group.The experiment lasted for 6 weeks.Body weight was measured each week,sugar preference was evaluated every 3 weeks,and behavior of rats was assessed through open field tests before model establishment and 6 weeks after model establishment.Animals were sacrificed after 6 weeks,brain tissues were obtained,and the expression of TPH-2 mRNA and the content of 5- HT in different areas of brain detected.Results After the beginning of stress experiment,the body weight of rats in group B and group C was significantly lower than that in group A(P <0.05).Rats in group B has significantly lower sugar preference than group A and group C(P < 0.05),and had higher activity.The content of 5- HT in hippocampus of rats in group B was higher than that in group A and group C,while there was significant difference between them(P< 0.05),The content of 5- HT in striatum of rats in group B and group C was lower than that in group A(P-< 0.05).The expression of TPH-2 mRNA in raphe nuclei of rats in group B was lower than that in group A(P <0.05).Conclusions Chronic stress may increase the content of 5-HT in hippocampus and decrease the expression of TPH-2 in raphe nuclei,while antidepressant may decrease the content of 5-HT in hippocampus without affecting the expression of TPH-2.更多还原