吗啡戒断后焦虑症状大鼠伏核和杏仁核突触结构可塑性

目的 探讨吗啡依赖戒断焦虑行为与大鼠伏核、杏仁核突触形态结构可塑性变化之间的相关性.方法 采用剂量递增法建立大鼠吗啡依赖模型,应用高架十字迷宫检测焦虑行为,应用透射电镜技术结合图像分析系统比较对照组、模型组和治疗组(每组均6只)大鼠伏核、杏仁核突触体视学、界面结构参数的数据.结果 (1)行为学:模型组开放臂的次数和时间均少于对照组和治疗组(P＜0.01或P＜0.05).(2)突触体视学:伏核模型组数密度(Nv)(1.012±0.036)个/μm3]较对照组(0.701±0.138)个/μm3]和治疗组(0.751±0.245)个/μm3]增加(P＜0.01),面密度(Sv)和突触连接带平均面积(S)3组间比较差异无统计学意义;杏仁核模型组Nv(0.427±0.178)个/μm3]较对照组(0.247±0.117)个/μm3]和治疗组(0.246±0.116)个/μm3]增加(P＜0.01或P＜0.05),模型组Sv(0.047±0.018)μm2/μm3]较对照组(0.030±0.012)μm2/μm3]和治疗组(0.030±0.015)μm2/μm3]增加(P＜0.01),模型组S(0.124±0.066)μm2]较对照组(0.157±0.119)μm2]和治疗组(0.159±0.114)μm2]减小(P＜0.05).(3)突触界面结构:伏核和杏仁核各自突触的突触后致密物厚度、突触活性区长度、突触间隙宽度和突触界面曲率在模型组、对照组和治疗组间比较差异均无统计学意义.结论 吗啡依赖戒断所产生的焦虑与伏核和杏仁核突触形态结构可塑性的改变有一定相关性.

Abstract：

Objective The possible correlations between morphological contracture and plastic variability of synaptic structure in nucleus accumbens and amygdala neurons were surveyed in anxious symptom rats suffered from morphine withdrawal. Methods The escalating doses of morphine and the elevated plus-maze were applied to validate anxiety-like behavior in rats. The electron microscope was applied to detect the parameters involving the synaptic stereology and structural plasticity of synaptic interface structure of the nucleus accumbens and amygdala neurons in the control group, the morphine-withdrawal group and the cured group ( n = 6 ), associated with the stereological ways. Results ( 1 ) Compared with the control group and the cured group, reductions of frequency and time of open-arm were observed in the morphine-withdrawal group ( P ＜ 0. 01 or P ＜ 0. 05 ). ( 2 ) Higher numerical density ( Nv ) ( 1. 012 ±0. 036 )/μm3] of synapses of nucleus accumbens was detected in the anxious rats ( P ＜ 0. 01 ) than in the controls ( 0. 701 ±0. 138 )/μm3] and the cured rats ( 0. 751 ±0. 254 )/μm3] . No significant difference between the surface density ( Sv ) and the mean profile area ( S ) of synapse of the nucleus accumbens was discovered. Compared with the control group ( 0. 247 ± 0. 117 )/μm3] and the cured one ( 0. 246 ±0. 116 )/μm3] , higher values of Nv ( 0. 427 ±0. 178 )/μm3] in amygdala were detected in anxious rats ( P＜0.01 or P＜0.05 ). Similarly, higher score of Sv ( 0.047 ±0.018 )μm2/μm3] in amygdala was observed in the anxious rats ( P ＜ 0. 01 ) than those of the control group ( 0. 030 ±0. 012 )μm2/μm3] and cured group ( 0. 030 ±0. 015 )μm2/μm3] . However, anxious rats ( 0. 124 ±0. 066 )μm2] appear to be lower S of synapse in amygdale ( P ＜ 0. 05 ) than those of the control group ( 0. 157 ±0. 119 )μm2] and the cured group ( 0. 159 ±0. 114 )μm2] . ( 3 )No significant difference among postsynaptic density, length of synaptic thickening, widths in synaptic interface structure on junctions and curvature of synaptic cleft region was detected in the nucleus accumbens and amygdala neurons. Conclusion In the present study, the results suggest that anxious rats suffered from morphine withdrawal could possibly be related to the plastic variability of synaptic morphological structure in nucleus accumbens and amygdale.

The plastic variability of synaptic structure of nucleus accumbens and amygdala in anxious rats suffered from morphine withdrawal

Objective The possible correlations between morphological contracture and plastic variability of synaptic structure in nucleus accumbens and amygdala neurons were surveyed in anxious symptom rats suffered from morphine withdrawal. Methods The escalating doses of morphine and the elevated plus-maze were applied to validate anxiety-like behavior in rats. The electron microscope was applied to detect the parameters involving the synaptic stereology and structural plasticity of synaptic interface structure of the nucleus accumbens and amygdala neurons in the control group, the morphine-withdrawal group and the cured group ( n = 6 ), associated with the stereological ways. Results ( 1 ) Compared with the control group and the cured group, reductions of frequency and time of open-arm were observed in the morphine-withdrawal group ( P ＜ 0. 01 or P ＜ 0. 05 ). ( 2 ) Higher numerical density ( Nv ) ( 1. 012 ±0. 036 )/μm3] of synapses of nucleus accumbens was detected in the anxious rats ( P ＜ 0. 01 ) than in the controls ( 0. 701 ±0. 138 )/μm3] and the cured rats ( 0. 751 ±0. 254 )/μm3] . No significant difference between the surface density ( Sv ) and the mean profile area ( S ) of synapse of the nucleus accumbens was discovered. Compared with the control group ( 0. 247 ± 0. 117 )/μm3] and the cured one ( 0. 246 ±0. 116 )/μm3] , higher values of Nv ( 0. 427 ±0. 178 )/μm3] in amygdala were detected in anxious rats ( P＜0.01 or P＜0.05 ). Similarly, higher score of Sv ( 0.047 ±0.018 )μm2/μm3] in amygdala was observed in the anxious rats ( P ＜ 0. 01 ) than those of the control group ( 0. 030 ±0. 012 )μm2/μm3] and cured group ( 0. 030 ±0. 015 )μm2/μm3] . However, anxious rats ( 0. 124 ±0. 066 )μm2] appear to be lower S of synapse in amygdale ( P ＜ 0. 05 ) than those of the control group ( 0. 157 ±0. 119 )μm2] and the cured group ( 0. 159 ±0. 114 )μm2] . ( 3 )No significant difference among postsynaptic density, length of synaptic thickening, widths in synaptic interface structure on junctions and curvature of synaptic cleft region was detected in the nucleus accumbens and amygdala neurons. Conclusion In the present study, the results suggest that anxious rats suffered from morphine withdrawal could possibly be related to the plastic variability of synaptic morphological structure in nucleus accumbens and amygdale.