海洛因慢性处理对大鼠脑内一氧化氮合酶阳性神经元数量和形态的影响

Effects of chronic heroin treatment on nitric oxide synthase positive neurons of brain in rats

目的观察不同浓度海洛因处理对大鼠伏隔核(NAc)、中央灰质背侧(CGd)一氧化氮合酶(NOS)阳性神经元数量和形态的影响。方法将32只SD大鼠随机分成4组,海洛因慢性处理后,采用还原型辅酶Ⅱ-黄递酶(NADPH-d)组织化学方法染色,观察不同浓度海洛因处理对大鼠NAc、CGd区NOS阳性神经元表达的影响。结果0.25mg·kg-1、1.0mg·kg-1海洛因慢性处理组NAc区(38.2±3.8)(36.8±1.9)、CGd区(65.3±1.3)(61.8±1.8)和0.05mg·kg-1海洛因慢性处理组NAC区(44.3±1.4)NOS阳性神经元细胞数较对照组NAc区(29.8±1.9)、CGd区(52.4±2.7)明显增多(P<0.05);0.05mg·kg-1海洛因慢性处理组CGd区(33.9±1.3)和1.0mg·kg-1海洛因慢性处理组CGd区(32.1±1.1)、NAc区(31.0±1.6)NOS阳性神经元胞体面积较对照组(40.8±0.8)有明显缩小(P<0.05);0.05mg·kg-1、1.0mg·kg-1组大鼠CGd区(49.2±2.1)(43.5±1.4)NOS阳性神经元轴突长度较对照组(58.2±3.6)明显变短(P<0.05),而三个处理组NAc区NOS阳性神经元轴突长度差异无显著性(P>0.05)。结论海洛因慢性处理能够引起CGd、NAc区NOS阳性神经元数量增多、胞体缩小、轴突长度变短,提示海洛因慢性处理对NOS阳性神经元有损伤作用,NOS参与了海洛因的依赖过程。

Objective To study the effects of chronic treatment with heroin at different doses on the expression of nitric oxide synthase（NOS） positive neurons in NAc and CGd of rats. Methods 32 SD rats were di- vided into four groups randomly, and treated with heroin chronically. The NOS positive neurons were stained by NADPH-diaphorased （NADPH-d） histochemistry. Image analysis technology was applied. Results After chronic treatment with heroin at doses of 0.05 mg · kg^-1 ,0.25 mg · kg^-1 or 1.0 mg · kg^-1 , the number of NOS positive neuron in both NAc （38.2 ± 3.8 ） （36.8 ± 1.9 ） and CGd （ 65.3 ± 1.3 ） （61.8 ± 1.8 ） was significantly more than that of the control group（ 29.8 ± 1.9） （52.4 ± 2.7 ） （ P〈 0.05 ）. Compared with the control group （40.8 ± 0.8 ）, the cell body area of NOS positive neuron decreased obviously in NAc （ 31.0 ± 1.6） and CGd （ 32.1 ± 1.1 ） of 1.0 mg · kg^-1 group, as well as 0.05 mg · kg^-1 group in CGd（33.9 ± 1.3） （P〈0.05）. After chronic treatment with heroin at doses of 0.05 mg · kg^1 （49.2 ± 2.1 ） and 1.0 mg · kg^-1 （43.5 ± 1.4）, the axon length of NOS positive neuron was apparently shorter than that of the control group in CGd（ P〈0.05）, however there isn＇t any significant differ among the heroin treatment groups and the control group （ 58.2 ± 3.6） in NAc. Conclusion Chronic heroin treatment could cause the structure change of NOS positive neurons, such as the increase in cell numbers, the shrinkage in cell bodies and the shorten in axon length, suggesting that neural injury exists during chronic herion dependence and NOS participates in the process of chronic heroin dependence.