大鼠甲醇中毒后体内的甲酸分布CSCD

目的研究大鼠甲醇中毒后血液及体内主要组织中甲酸的浓度及分布特点。方法将SD大鼠分为对照组、中毒3 d组和中毒7 d组,中毒模型按照首剂量8 m L/kg给予大鼠甲醇灌胃,24 h后给予减半剂量4 m L/kg再次灌胃,在首次灌胃后的3 d和7 d将大鼠引颈处死,采心血并提取肝、肾、脑、心和胃组织,利用高效液相色谱仪检测其中的甲酸含量。结果甲酸在组织中的浓度高于血液中;与中毒3d组比较,中毒7d组脑和胃组织内的甲酸质量浓度有一定的增加趋势,而肝和肾组织中的甲酸质量浓度有所下降(P<0.05)。结论高效液相色谱法可以作为一种准确检测甲酸的定性定量方法。大鼠甲醇中毒后,其代谢产物甲酸在血液及组织中均有蓄积,在器官组织中的蓄积更显著。     

大鼠甲醇中毒后体内的甲酸分布

目的研究大鼠甲醇中毒后血液及体内主要组织中甲酸的浓度及分布特点。方法将SD大鼠分为对照组、中毒3 d组和中毒7 d组,中毒模型按照首剂量8 m L/kg给予大鼠甲醇灌胃,24 h后给予减半剂量4 m L/kg再次灌胃,在首次灌胃后的3 d和7 d将大鼠引颈处死,采心血并提取肝、肾、脑、心和胃组织,利用高效液相色谱仪检测其中的甲酸含量。结果甲酸在组织中的浓度高于血液中;与中毒3d组比较,中毒7d组脑和胃组织内的甲酸质量浓度有一定的增加趋势,而肝和肾组织中的甲酸质量浓度有所下降(P0.05)。结论高效液相色谱法可以作为一种准确检测甲酸的定性定量方法。大鼠甲醇中毒后,其代谢产物甲酸在血液及组织中均有蓄积,在器官组织中的蓄积更显著。     

毒鼠强中毒大鼠脑GABA及GABAAR-α1的表达

目的探讨毒鼠强中毒大鼠脑GABA及GABAAR-α1表达的变化及可能机制。方法健康Sprague-Dawley(SD)大鼠60只,随机分为正常对照组、空白对照组、高剂量中毒组和低剂量中毒组,每组5只。高剂量中毒组每只以1.0mg/kg的剂量用毒鼠强悬浊液灌胃,低剂量中毒组每只以0.1mg/kg的剂量用毒鼠强溶液灌胃制作中毒模型。应用免疫组化技术和图像分析仪对GABA及GABAAR-α1的表达情况和变化规律进行研究。结果(1)正常大鼠脑组织内GABA及GABAAR-α1表达较为广泛,维持在中等水平;(2)高剂量中毒组脑内GABA及GABAAR-α1表达均下降;(3)低剂量中毒组脑内GABA表达先下降,于中毒后6h降至最低,后表达开始增加,3d时接近对照组水平,5～7d达高峰,10d时仍高于对照组;(4)低剂量中毒组脑内GABAAR-α1表达先下降,于中毒后6～12h降至最低,后表达开始增加,7～10d时接近对照组水平。结论(1)高剂量毒鼠强中毒情况下,GABA及GABAAR-α1表达均下降;(2)大鼠脑GABA及GABAAR-α1表达改变与毒鼠强中毒的发生机制密切相关。     

大鼠毒鼠强中毒内脏器官Caspase-3与Bcl-2蛋白的表达

目的探讨大鼠毒鼠强中毒的病理机制。方法SD大鼠60只,随机分正常对照组、空白对照组、高剂量中毒死亡组、低剂量中毒组,高剂量中毒死亡组以1.0mg/kg毒鼠强悬浊液灌胃,低剂量中毒组以0.1mg/kg体重毒鼠强悬浊液灌胃。用免疫组织化学技术对中毒大鼠器官检测caspase-3与Bcl-2蛋白的表达,用图像分析技术对检测结果进行分析。结果各器官caspase-3与Bcl-2蛋白的表达变化规律基本相似,即高剂量中毒组大鼠caspase-3与Bcl-2蛋白均呈较强的阳性表达,低剂量中毒组大鼠,Bcl-2与caspase-3于中毒30min后表达不明显,3h时,可见较为明显的阳性信号,Bcl-2在6h～3d达高峰,随后表达下降;caspase-3在24h～5d达峰值,随后下降。Bcl-2峰值早于caspase-3出现。结论Bcl-2与caspase-3参与了毒鼠强中毒的病理生理过程。     

大鼠闭合性脑损伤后MAP-2的时序性表达

目的探讨大鼠闭合性颅脑损伤后脑组织微管相关蛋门－2（MAP－2）表达变化规律。方法建立大鼠闭合性颅脯挫伤模型,64只Wistar大鼠随机分为损伤后0．5h、6h、12h、ld、3d、7d、14d7个损伤组及对照组,每组8只。应用免疫组化和蛋h印记Western blot法及图像分析技术,检测脑挫伤后各设定时间点挫伤脯组织中MAP－2的变化。结果免疫纽化染色显示：对照组大鼠脑组织中可见MAP－2阳性表达;实验组伤后0．5h,挫伤灶及周同MAP－2阳性表达下降,伤后6h阳性表达降至最低,伤后12h,阳性表达逐渐增多,伤后14d,仍保持较高水平;蛋白印记结果与免疫组化结果一致。统计学分析显爪：MAP－2的表达各损伤组与对照组比较,差异均有统计学意义（P〈0．05）,伤后12h、3d及14d与上…组比较,差异有统计学意义（P〈0．05）。结论大鼠脑挫伤后14d内,MAP－2存脑组织挫伤灶及其周同呈现先减少后逐渐增多的表达变化,可作为推断脑挫伤经过时间的参考指标之一。     

大鼠弥漫性脑损伤后c-jun和GFAP表达的研究

目的探讨即早基因c-jun和胶质纤维酸性蛋白（GFAP）在弥漫性脑损伤（DBI）中的表达规律。方法采用Marmarou方法制作大鼠DBI模型，将65只SD大鼠随机分为DBI组及对照组。用免疫组织化学技术（SABC）及图像分析方法观察大鼠DBI后15min、30min、1h、3h、6h、12h、24h、2d、3d、4d、6d脑组织内c-jun和GFAP表达规律，所得数据经SPSS10．0统计软件处理。结果对照组大鼠脑组织内未见c-jun阳性表达，可见少量GFAP表达。DBI15min即可在脑组织内观察到c-jun表达，而GFAP蛋白的表达则在DBI后6h增加。随着损伤经过时问的延长，c-jun与GFAP阳性细胞数及阳性表达范围逐渐扩大，c-jun表达在DBI后6h达高峰（P〈0．01），其后逐渐下降，伤后2d减退；GFAP阳性产物则在伤后4d左右达高峰（P〈0．01），其后呈下降的趋势。结论应用免疫组织化学方法检测c-jun与GFAP可作为诊断DBI的参考指标，二者在不同时段内表达所呈现出的时序性规律对损伤时间的推测也具有实际应用价值。     

大鼠骨骼肌损伤后PMN、MNC及FBC百分率与损伤时间关系

目的：研究大鼠骨骼肌机械性损伤后不同时间点多形核白细胞（polymorphonuclear leucocytes , PMN）、单个核细胞（mononuclear cells,MNC）及成纤维样细胞（fibroblastic cells,FBC）百分率的变化。方法建立大鼠骨骼肌机械性损伤动物模型,随机分为伤后6h、12h、1d、3d、7d、10d、14d及正常对照组。应用HE染色法和图像分析检测大鼠骨骼肌损伤后不同时间点PMN、MNC及FBC百分率。结果伤后6~12 h,损伤区内可见PMN和MNC浸润,PMN百分率达到峰值;伤后1 d,损伤区内主要以MNC浸润为主,MNC百分率达到峰值,而PMN百分率开始下降;伤后3~7 d,FBC百分率开始逐渐增加,PMN和MNC百分率则逐渐下降;伤后10~14 d,FBC百分率达到峰值。结论大鼠骨骼肌损伤区内PMN、MNC及FBC百分率呈时间规律性变化,有望成为骨骼肌损伤时间推断的参考指标。     

大鼠弥漫性轴索损伤后NGF表达

目的研究大鼠弥漫性轴索损伤后神经生长因子（NGF）表达的时间变化规律及意义。方法采用SD雄性大鼠复制弥漫性轴索损伤（DAI）模型,分别于伤后1、3、6、12、24、48h和3、7d取脑组织,应用免疫组织化学法对DAI后不同时间段大脑皮层、丘脑、小脑和海马部位NGF的表达变化进行观察并与正常组、假手术组对照。结果正常及假手术组大鼠大脑皮层、丘脑、小脑、海马均有少量NGF的表达。打击后1hNGF表达增强,12h达高峰,3d开始下降,7d降至正常。结论NGF参与弥漫性轴索损伤后的修复：NGF的时序性变化有望成为法医学脑损伤时间推断的客观指标。     

大鼠脑挫伤后脑组织β-APP表达的研究

目的观察大鼠实验性脑挫伤后CNS内β-APP蛋白表达时空性规律.方法采用自由落体撞击法致大鼠脑挫伤模型,用免疫组化技术观察伤后β-APP蛋白在不同时间（0.5 h、2 h、6 h、12 h、24h、3 d、7 d、14 d）的表达情况,并用计算机图像分析技术作定量统计分析.结果（1）皮质内β-APP蛋白在伤后表达呈一定波动性,0.5 h表达明显增加后,逐渐下降,12 h降至最低,低于对照组,随后再次表达增加,3 d达高峰;（2）伤后24h海马区β-APP表达开始逐渐下降,3 d降至最低,14d回到对照组水平;（3）齿状回（DG）内β-APP蛋白在伤后12 h低于对照组.结论实验性脑挫伤后皮质β-APP表达时序性规律可为脑损伤时间推断提供一个新的参考指标,但海马区及DGβ-APP变化规律在脑损伤时间推断方面价值不大.     

不同环境条件下大鼠死后皮肤大体和组织学改变

目的研究观察大鼠在不同环境条件下死后不同时间其皮肤大体、组织学的改变,为推测较长的死后间隔时间建立实验动物依据。方法观察雌性SD大鼠在不同环境条件下的死后变化,并间隔一定死后时间取皮、染色和镜下观察。结果死后发生骨、软组织分离,A组约需35d,B组需13d。皮肤有形细胞成分和附属器完全分解破坏,A组约20d,B组7d。胶原纤维在A组死后40d（B组12d）仍有部分保留完整。结论环境温度差异是造成A、B两组发生死后改变时程不同的主要因素,利用皮肤大体、组织学改变可望较系统和准确的推测晚期死亡时间。     

甲基苯丙胺中毒大鼠纹状体小胶质细胞的激活特性

目的研究甲基苯丙胺（methamphetamine,MA）中毒动物模型纹状体内小胶质细胞（microglia,MG）的激活特性。方法SPF级雄性Wistar大鼠,随机分为对照组和实验组,每组24只。实验组采取腹腔注射MA（15 mg/kg×8次,每次间隔12 h）;对照组按上述给药方式每次注射等量的生理盐水。两组分别于首次注射后第0.5、1、2、3、4、5、6和7天共8个时间点纹状体取材,进行CD-11b抗体免疫组化染色和超微结构观察形态学变化,另对免疫组化染色结果进行细胞激活率计算,并进行统计。结果光、电镜下,各时间点对照组的MG胞体瘦小、突起细长,呈＂细分枝状＂,胞核浓缩,胞质内细胞器稀少;实验组MG胞体变大、突起变短或消失,呈＂灌木丛状＂或＂阿米巴状＂,胞核电子密度降低,胞质内细胞器丰富。对照组各时间点MG的激活率维持在0.15水平以下,且随着观察时间的延长无明显变化趋势;而实验组MG的激活率与对照组相比,第1～7天均显著升高（P〈0.001）。结论MA的刺激可导致MG明显激活。     

Electroretinogram and Histopathologic Changes of the Retina after Methanol Intoxication

In order to study the functional and structural alterations of the retina in SD rat model after methanol intoxication,35 rats were divided randomly into five groups administrated with saline,3-day high dose,7-day high dose,3-day low dose and 7-day low dose methanol separately.The retinal function of each group was assessed by flash electroretinogram(F-ERG) 3 and 7 days after methanol poisoning.The microstructure and ultrastructure of the retina were observed at the same time.The high-dose methanol intoxication induced irreversible retinal functional and structural damages 3 days after poisoning,which included prolonged latency and reduced amplitude of the Max-reaction of F-ERG.These injuries were aggravated 7 days after poisoning.Meanwhile,the latency and amplitude of the Cone-reaction of F-ERG were also affected 3 days after poisoning,but there were no further worsening tendency 7 days after poisoning.The retinal histological analysis showed cellular edema,heteromorphy and disarrangement,tissular loosen of the inner nuclear layer and photoreceptors layer.The mitochondrial damage began at the photoreceptors layer and developed further into the inner nuclear layer.The low-dose methanol intoxication only caused transient damage of the retina.Our results showed that the function and structure of the photoreceptor and inner nuclear layer were the primary target of methanol intoxication and that the rod cells were more sensitive to methanol intoxication than the cone cells.The mitochondrial damage developed from outer layer to inner layer of the retina.     

大鼠脑挫伤后NTE与COX-2表达随时间的变化

目的观察大鼠脑挫伤后脑组织NTE和COX-2的表达变化，并评价其法医学的意义。方法健康SD大鼠48只，随机分成正常对照组、手术对照组、挫伤组（按挫伤后处死时间再分为lh、12h、1d、3d、7d、14d共6个组）每组6只。以自由落体撞击法制作脑挫裂伤模型；应用免疫组化方法检测COX-2和NTE在脑组织中的表达情况；用SPSS13．0软件分析COX-2和NTE的表达情况与脑挫伤后存活时间的相关性。结果正常对照组和假手术绢NTE和COX-2均呈低水平表达，脯挫伤组伤后NTE和COX-2表达逐渐增强，均于1d达到高峰，至14d时COX-2表达降至正常对照组水平，而NTE仍高于正常对照组水平；挫伤各组与正常对照组比较，除1h组灰度值无统计学差异（P〉0．05）外，其余各组均有明显差异（P〈0．01）。结论脑挫伤后脑组织NTE和COX-2的表达均呈现先增强后下降的趋势，其表达规律有望为脑挫伤诊断及损伤时间推断提供参考。     

TMS-MEP评价大鼠脊髓损伤后运动功能障碍程度的研究

目的探讨采用TMS-MEP评价大鼠脊髓损伤后运动功能障碍的可行性,并评价其在法医学中的应用价值。方法 SD雌性大鼠100只,分为3个损伤组、1个假手术组和1个正常对照组。损伤组采用Allen’s打击装置制作脊髓损伤模型;各组均于实验前、损伤后1d、1周、2周、4周,根据大鼠脊髓运动功能评定标准进行运动功能评分,并在70%刺激强度下记录腓肠肌的TMS-MEP;采用SPSS 19.0软件进行数据处理,单因素方差分析比较组间差异。结果损伤组随打击能量的增加,脊髓损伤程度加重,双下肢运动功能缺失明显,与正常对照组、假手术组和实验前之间均存在显著性差异（P〈0.05）。损伤组MEP潜伏期和波幅较正常对照组均延长,差异具有显著意义（P〈0.05）。TMS-MEP回归方程Y=0.465 1X＋4.602 4（R2=1,P〈0.001）,回归得出的结果与观察评分之间存在高度吻合。结论采用本文方法可为肌力的评定提供客观依据,有望在法医鉴定实践中应用。     

可卡因对性成熟期雄性大鼠生殖功能的损害

目的探讨可卡因对性成熟期雄性大鼠生殖功能的影响及其作用机制。方法选用性成熟期健康雄性SD大鼠30只，随机分为实验组和对照组，每组15只。实验组大鼠以15mg／kg剂量每天皮下注射可卡因28d。观察动物体质量、睾丸质量改变，检测血液中激素含量的变化．利用原位缺口末端标记（TUNEL）法检测睾丸细胞的凋亡，免疫组化方法检测睾丸Fas基因的表达。结果（1）实验组大鼠体质量、睾丸质量明显低于对照组（P〈0．05）；（2）实验组与对照组相比，睾酮含量明显降低（P〈O．05）：（3）实验组睾丸细胞凋亡较对照组明显增多（P〈0．05），Fas基因表达明显增加（P〈0．05）．且Fas基因阳性表达与睾丸细胞的凋亡指数呈正相关（r=0．9012，P〈O．05）。结论可卡因可致大鼠生殖器官发育和生殖内分泌功能损害．造成生精细胞凋亡．增殖能力下降．可能与Fas介导的睾丸生精细胞凋亡机制有关。     

曲马多中毒死亡后GABAA受体α1和GABAB受体1亚型在延髓孤束核和疑核中的表达

目的 观察曲马多中毒死亡后人脑延髓孤束核和疑核中γ-氨基丁酸(gamma-amino butyric acid,GABA)A受体α1亚型(GABAAα1)和B受体1亚型(GABAB1)的表达变化,探讨曲马多中毒死亡的机制.方法 应用免疫组织化学方法,观察比较曲马多中毒死亡人脑与非中毒原因死亡人脑延髓孤束核和疑核的GAB...     

Expressions of GABA and GABA(A)R-alpha1 in the brain of rats poisoned by tetramine

OBJECTIVE: Expressions of GABA and GABA(A)R-alpha1 in the brain of rats poisoned by Tetramine were analyzed to explore the intoxication mechanism. Methods Sixty rats were randomly divided into control, sham poisoned, high-dose poisoned (1.0 mg/kg tetramine) and low-dose poisoned (0.1 mg/kg) groups. The expressions of GABA and GABA(A)R-alpha1 in the brain of the poisoned rats were detected and analyzed by immunohistochemistry and imaging analyzer. Results The expressions of both GABA and GABA(A)R-alpha1 were diffusely seen in the brains of the control and shame poisoned rat groups with a moderate expression level, whereas the expressions of both GABA and GABA(A)R-alpha1 were decreased in the brains of the high-dose poisoned group. In the low-dose poisoned rat group, the expression of GABA initially decreased and reached its lowest level 6 hours after poisoning, and then started to show an increase and reached the level of control groups at day 3. The expressions level reached its peak at days 5-7 after poisoning and remained above the level of control groups till 10 days after poisoning. Similarly, the expression of GABA(A)R-alpha1 in the brains of the low-dose poisoned group initially decreased and reached its lowest level 6-12 hrs after poisoning, and then started to increase and reached the level of control groups at days 7-10 after poisoning, respectively. Conclusion The expression of both GABA and GABA(A)R-alpha1 decreased in the brains of the high-dose poisoned rat group and these changes of GABA and GABA(A)R-alpha1 expressions may be associated with underlying mechanism of tetramine poisoning.     

甲卡西酮对大鼠血浆代谢谱变化研究

目的 应用代谢组学技术研究腹腔注射甲卡西酮大鼠血浆代谢谱的变化,筛选出可用于甲卡西酮吸毒法医学鉴定的入体生物标志物.方法 SD大鼠随机分成低剂量甲卡西酮组(腹腔注射甲卡西酮溶液3mg/kg)、中剂量甲卡西酮组(腹腔注射甲卡西酮溶液12mg/kg)和对照组(腹腔注射等量生理盐水),注射3min后收集大鼠眼眶血,应用超高效...     

Post-mortem analysis of formic acid disposition in acute methanol intoxication

Fifteen cases of fatal massive methanol intoxication have been investigated. Victims received either no treatment or ethanol therapeutic treatment. Methanol poisoning cases were classified in three groups according to survival time: more than 3 days (group 1), up to 3 days (group 2) and few hours (group 3). Body distribution of methanol and formic acid, as the main metabolite, was analyzed in blood and in different organs (brain, kidney, lung and liver). Relationships between formic acid concentration in the different tissues, survival time and type of treatment applied to victims were studied. Formic acid in blood and tissues was analyzed by head space gas chromatography (head space-GC) with FID detector, previous transformation in methyl formate, essentially as described by Abolin. Formic acid concentration was between 0.03 and 1.10g/l in the samples under study. A good correlation between blood and brain, but poor between blood and the remaining tissues was found. Obtained data suggested that the use of blood and brain could help to improve the analysis of formic acid intoxication. The best correlation among organs was found between lung and kidney for all groups (r(2)=0.91, 0.84 and 0.87, corresponding to groups 1, 2 and 3, respectively). Lethality index was defined as LI = (concentration of formic acid in blood in (g/l)/0.5) x 100, taking into account that 0.5g/l is the concentration reported by Mahieu in severe methanol poisoning. LI parameter was used to estimate formic acid incidence on the lethality of methanol poisoning cases. LI showed a good correlation with total formic acid concentration of the different tissues analyzed (r(2)=0.80). Furthermore, LI allowed us to discriminate between individuals that received therapeutic treatment and survived different periods. LI>100 indicated a severe intoxication and short survival time if the victim was assisted with ethanol therapy and hemodialysis was not applied. With regard to victims who received no therapeutic treatment and died in few hours, LI was in the range 40-100. LI was below 40 for individuals that survived more than 3 days and hemodialysis was not performed. Results showed the importance of performing formic acid analysis to diagnose severe methanol intoxication in post-mortem cases.