构建慢传输型便秘与慢性应激抑郁模型大鼠:揭示便秘与抑郁的关系

背景:临床上便秘患者常常伴有抑郁情绪,抑郁患者也常常伴有便秘症状,其机制不清。目的:通过建立动物模型了解便秘和抑郁的关系。方法:将60只SPF大鼠随机分成3组:正常组、慢性应激抑郁模型组和慢传输便秘模型组。慢传输便秘模型组大鼠每日给予复方地芬诺酯灌胃,给药剂量为8 mg/kg,持续时间120 d。实验第100天开始随机予慢性应激抑郁模型组不可预见刺激21 d。正常组大鼠常规饲养。每周记录1次大鼠粪便粒数、粪便干质量及大鼠体质量。建模成功后检测各组大鼠粪便粒数、粪便干质量、首粒黑便排出时间、糖水偏爱百分比、旷场实验行为学得分、强迫游泳时间并进行统计分析。结果与结论:慢性应激抑郁模型组粪便粒数较正常组少(P=0.00)、首粒黑便排出时间较正常组长(P=0.00);粪便粒数较慢传输便秘模型组多(P=0.00),首粒黑便排出时间较慢传输便秘模型组短(P=0.00)。慢传输便秘模型组的液体消耗量、糖水偏爱百分比、旷场实验水平得分和垂直得分、强迫游泳时间均较正常组均差异无显著性意义(P>0.05),但均高于慢性应激抑郁模型组(P<0.01)。结果证实,实验成功建立的慢性应激抑郁模型大鼠可表现出便秘现象,而慢传输便秘模型大鼠未能表现出抑郁现象,表明抑郁可以导致便秘,但便秘不一定会导致抑郁。

山楂叶提取物抗抑郁作用的初步研究

目的探讨山楂叶提取物抗抑郁作用。方法将小鼠随机分为山楂叶提取物高、中、低剂量组(1.0、0.5、0.25 g/kg)、百合皂苷组(0.05 g/kg)、氟西汀(0.004 g/kg)组和正常对照组(等容生理盐水),观察小鼠悬尾不动时间、强迫游泳不动时间和拮抗利血平降低小鼠体温的变化。结果与对照组相比,山楂叶提取物高、中、低剂量组、百合皂苷组和氟西汀组小鼠悬尾不动时间和强迫游泳不动时间均明显缩短,组间比较差异有统计学意义(P <0.05或P <0.01);山楂叶提取物中、低剂量组、百合皂苷组合氟西汀组小鼠体温变化明显减小,组间比较差异有统计学意义(P <0.05)。结论山楂叶提取物具有一定的抗抑郁作用。

Forced swimming stress does not affect monoamine levels and neurodegeneration in rats

Objective The current study was aimed to investigate the correlations between immobility time in the forced swimming test （FST, a behavioral indicator of stress level） and hippocampal monoamine levels （markers of depression）, plasma adrenalin level （a peripheral marker of stress） as well as fluoro-jade C staining （a marker of neurodegeneration）. Methods Male Sprague-Dawley rats were subjected to acute, sub-chronic （7 d） or chronic （14 d） FSTs and immobility time was recorded. Levels of noradrenalin, serotonin and dopamine in the hippocampus, and adrenalin level in the plasma were quantified by high-performance liquid chromatography with electrochemical detection. Brain sections from rats after chronic forced swimming or rotenone treatment （3 mg/kg subcutaneously for 4 d） were stained with fluoro-jade C. Results The rats subjected to swimming stress （acute, sub-chronic and chronic） showed long immobility times [（214 ± 5）, （220 ± 4） and （231 ± 7） s, respectively], indicating that the animals were under stress. However, the rats did not exhibit significant declines in hippocampal monoamine levels, and the plasma adrenalin level was not significantly increased compared to that in unstressed rats. The rats that underwent chronic swimming stress did not manifest fluoro-jade C staining in brain sections, while degenerating neurons were evident after rotenone treatment. Conclusion The immobility time in the FST does not correlate with markers of depression （monoamine levels） and internal stress （adrenalin levels and neurodegeneration）, hence this parameter may not be a true indicator of stress level.