Cyanide-induced hyperthyroidism in male Wistar rats

Background:

Cyanide is one of the major environmental pollutants termed thyroid disruptor. Regardless of its origin, it is a primary toxic agent. This study was designed to understand the impact of prolonged low dose cyanide exposure on the structure and function of the thyroid gland.

Materials and Methods:

Twelve F1 male Wistar rats were used for this study. They were divided into two groups of six animals each. The first group served as the control group and received 0.25M sucrose while the second group being the treated group received 2 mg/kg body weight (BW) potassium hexacyanoferrate III solution. The treatment duration was 56 days following which the animals were sacrificed by cervical dislocation. Blood samples were drawn to determine serum FT3, FT4 and thyroid stimulating hormone (TSH) levels. The thyroid gland was also excised and processed for light microscopic studies.

Result:

An increase in serum FT3 and FT4 with decrease serum TSH was obtained in the treated group. Application of one-way analysis of variance (ANOVA) statistical analysis showed that there were highly significant differences (P < 0.05) in the activities of FT3, FT4 and TSH when compared with those of the control group. Light microscopic examination of thyroid gland from the treated group revealed marked epithelial hyperplasia with cellular degeneration and scanty cytoplasm while the control group revealed normal thyroid architecture.

Conclusion:

Results obtained revealed that hyperthyroidism was induced by cyanide.     

SD与Wistar大鼠跳台反射法动物行为学模型建立的比较

目的:比较SD与Wistar两种不同品系大鼠在跳台反射法中的不同反应,为建立跳台反射法耳鸣动物行为学模型前动物的筛选提供一种实验依据.方法:健康雄性SD大鼠和Wistar大鼠各20只,分为2组.动物于隔音室内进行条件反射训练,各频率背景噪声均<25dBSPL,训练时将大鼠置于跳台仪内,箱顶扬声器给予10kHz,70dBSPL的白噪声作为条件刺激.持续时间为20秒,非条件刺激为大鼠足底电击(50v),持续时间至多17秒(与声刺激间步进行),条件刺激和非条件刺激出现的时间间隔为3秒.连续训练三周,分别记录两组动物每次在给声期间及刺激间期跳上跳台的次数,比较SD大鼠与Wistar大鼠的正确反应率.结果:SD大鼠的正确反应率为(14.4±19.1)%,Wistar大鼠的正确反应率为(15.4±17.7)%.经卡方检验统计,SD人鼠与Wistar大鼠的正确反应率无显著性差异(P>0.05).结论:SD大鼠与Wistar大鼠在跳台反射法实验中的正确反应率未见显著性差异,但是与文献报道相比,大鼠在改良的跳台反射中的正确反应率偏低.     

血管内皮生长因子在糖尿病大鼠脉络膜视网膜的表达

目的 在糖尿病的不同病程中,通过免疫组织化学方法观察血管内皮生长因子(vessel endothelial growthfactor,VEGF)在糖尿病大鼠脉络膜中表达的时间、部位,比较正常大鼠及糖尿病大鼠视网膜、脉络膜组织中VEGF的表达情况.方法 选取健康雄性Wistar大鼠,采用随机数字表法分成糖尿病组和正常对照组,用链脲佐菌素(STZ)大剂量一次性腹腔注射诱导1型糖尿病模型.取不同组、不同时期大鼠视网膜脉络膜,利用免疫组织化学方法,检测VEGF蛋白质的表达情况.结果 ①糖尿病1个月组(M1)、血糖恢复组(Mh)大鼠视网膜脉络膜VEGF蛋白质的表达与正常对照组(MO)无明显区别.②糖尿病2个月组(M2)脉络膜可见VEGF蛋白质的阳性表达(33.3%),视网膜上VEGF蛋白质的阳性表达与正常对照组无明显区别.③糖尿病3个月组(M3)脉络膜VEGF蛋白表达阳性(55.6%),视网膜的内核层及节细胞层VEGF蛋白表达阳性与正常对照组(33.3%)比较有明显差异.④糖尿病4个月组(M4)脉络膜VEGF蛋白表达阳性(66.7%),视网膜的内界膜、内核层、外核层及节细胞层VEGF蛋白表达阳性(77.8%).⑤糖尿病5个月组(M5)脉络膜VEGF蛋白表达阳性(88.9%),视网膜全层均有VEGF蛋白阳性表达(88.9%).VEGF在脉络膜和视网膜的阳性染色密度随病程逐渐增加(P＜0.05).结论 VEGF在大鼠脉络膜视网膜中的表达与病程有关,VEGF蛋白在脉络膜的表达先与视网膜.     

Evaluation of embryonic alcoholism from auditory event-related potential in fetal rats

Auditory event-related potential (AERP) is a kind of electroencephalography that measures the responses of perception, memory and judgement to special acoustic stimulation in the auditory cortex. AERP can be recorded with not only active but also passive mode. The active and passive recording modes of AERP have been shown a possible application in animals.1,2 Alcohol is a substance that can markedly affect the conscious reaction of human. Recently, AERP has been applied to study the effects of alcohol on the auditory centers of the brain. Some reports have shown dose-dependent differences in latency, amplitude, responsibility and waveform of AERP between persons who have and have not take in alcohol.3,4 The epidemiological investigations show that the central nervous function of the offspring of alcohol users might be also affected.5,6 Because the clinic research is limited by certain factors, several animal models have been applied to examine the influences of alcohol on consciousness with AERP. In the present study, young rats were exposed to alcohol during fetal development and AERP as indicator was recorded to monitor the central auditory function, and its mechanisms and characteristics of effects of the fetal alcoholism on auditory center function in rats were analyzed and discussed.     

Evaluation of embryonic alcoholism from auditory event-related potential in fetal rats

Auditory event-related potential (AERP) is a kind of electroencephalography that measures the responses of perception, memory and judgement to special acoustic stimulation in the auditory cortex. AERP can be recorded with not only active but also passive mode. The active and passive recording modes of AERP have been shown a possible application in animals. Alcohol is a substance that can markedly affect the conscious reaction     

酮康唑对泮托拉唑在大鼠体内的药动学的影响

目的 研究酮康唑对泮托拉唑在大鼠体内药动学的影响,为临床合理用药提供参考.方法 12只大鼠随机分为实验组和对照组,灌胃给予泮托拉唑,实验组于给药前2h腹腔注射酮康唑,以高效液相色谱法测定泮托拉唑血药浓度,采用DAS软件计算药动学参数,以SPSS软件对组间各参数进行统计分析.结果 两组达峰时间和峰浓度相似(P>0.05),实验组的半衰期T1/2和曲线下面积AUCO→∞明显大于对照组(P<0.05),表现清除率CL/F则明显小于对照组(P<0.05).结论 肝药酶抑制药酮康唑可减弱大鼠对泮托拉唑代谢能力.     

大鼠急性实验性变态反应性脑脊髓炎模型的建立

目的建立大鼠急性实验性变态反应性脑脊髓炎(EAE)模型.方法采用豚鼠脊髓和福氏完全佐剂混合乳剂一次性注入Wistar大鼠双足垫和尾部,同时腹腔注射左旋咪唑诱导大鼠发生EAE.观察发病情况;HE染色观察病理变化;Loyez氏髓鞘染色法观察髓鞘改变.结果空白对照组大鼠均未出现症状,HE染色大脑白质及脊髓无炎性细胞浸润;Loyez氏染色未见髓鞘脱失;模型组临床症状发生率为87.5%,HE染色见大脑白质及脊髓血管周围有大量炎性细胞浸润;Loyez氏染色见部分脱髓鞘改变.结论用豚鼠脊髓髓鞘蛋白和福氏完全佐剂混合乳剂同时辅以左旋咪唑成功地诱导Wistar大鼠发生急性EAE.     

甲醛对雄性Wistar大鼠生殖毒性的影响研究

目的:探索不同剂量的甲醛对雄性大鼠精子畸形率、骨髓微核率、血清睾酮水平以及睾丸组织的影响。方法:选择性成熟Wistar大鼠40只随机分成5组:0.9%氯化钠注射液组（阴性对照组）和高、中、低剂量甲醛染毒组（20 mg·kg-1·d-1、2 mg·kg-1·d-1、0.2 mg·kg-1·d-1）及50 mg·kg-1·d-1环磷酰胺组（阳性对照组）。通过腹腔注射染毒1周,测定血清睾酮水平,染毒结束后2 d摘眼球采血,颈椎脱臼法处死大鼠,统计精子畸形率和骨髓微核率,对大鼠睾丸做石蜡组织切片,观察睾丸组织损伤情况。结果:精子畸形率:与阴性对照组比较,中、低剂量染毒组精子畸形率上升（P<0.05）,高剂量染毒组和阳性对照组精子畸形率上升更明显（P<0.01）;骨髓微核率:与阴性对照组比较,中、低剂量染毒组骨髓微核率上升不明显（P>0.05）,高剂量染毒组和阳性对照组上升明显（P<0.01）;血清睾酮水平:与阴性对照组比较,高、中、低剂量染毒组和阳性对照组血清睾酮水平均明显降低（P<0.01）。睾丸石蜡切片显示高剂量染毒组组织损伤严重。结论:甲醛可以引起雄性大鼠精子畸形,增加骨髓微核率,降低血清睾酮水平,对雄性大鼠具有一定的生殖及遗传毒性。     

大鼠性激素分泌的增龄性改变

目的　探讨Wistar大鼠性激素水平及HPG轴组织内过氧化物堆积的增龄性改变 ,为研究衰老的分子机制提供依据。方法　检测 3、6、12、18、2 1月龄Wistar大鼠下丘脑、垂体、卵巢 (雌性 )、睾丸 (雄性 )各组织内丙二醛含量以及血浆雌二醇 (E2 )、睾酮 (T) ,与上一月龄组指标作比较。结果　随月龄增长 ,雄性大鼠血浆睾酮及雌性大鼠血浆雌二醇水平逐渐下降 ,各组与上一月龄组比均相差显著 (P <0 0 1～ 0 0 5 ) ;大鼠下丘脑、垂体、性腺组织内的MDA含量明显增多 ,除 6月龄组与 3月龄组比无统计学意义外 ,其余各组与上一月龄组比均相差显著 (P <0 0 1～ 0 0 5 )。结论　生殖腺轴组织内脂质过氧化程度与性激素分泌的增龄性改变可能有关 ,脂质过氧化物的堆积有可能影响性激素的分泌     

链脲佐菌素致大鼠高血糖模型的实验研究

目的 探讨链脲佐菌素(streptozocin,STZ) 所致Wistar大鼠高血糖稳定模型的最佳实验条件.方法 应用STZ腹腔注射制备大鼠高血糖模型,计算成模率和死亡率.结果 采用一次给药法,分为不同剂量组(40mg/kg;50mg/kg;60mg/kg),其中50mg/kg剂量组成模率较好.采用两次给药法,第一次给予10mg/kg,隔1天分别给予以下剂量(40mg/kg,50mg/kg,60mg/kg),其中第一次10mg/kg,第二次50mg/kg剂量组成模率最高.两次给药法相对应剂量组成模率比一次给药法高.日照时间对成模率及死亡率均有影响.日照时间短,成模率明显降低,而且死亡率明显增高.结论 用STZ制备糖尿病模型是一种稳定可靠的方法.实验选取雄性Wistar大鼠体重190～220g,在日照时间充足的条件下饲养.给药方式采取两步给药法,剂量为10mg/kg,隔1天给予50mg/kg,其成模率最高.     

ENaCs mRNA在自发性高血压大鼠和Wistar大鼠组织中的差异表达

目的检测自发性高血压大鼠（SHR）和Wistar大鼠的ENaCs在mRNA水平的表达差异,探讨机械敏感性离子（Mechanosensitive Ion Channels,MS）对动脉压力感受器重调的作用。方法SHR大鼠和Wistar大鼠各6只,分别取左侧颈动脉窦、主动脉弓,异硫氰酸胍-酚氯仿法抽提总RNA。采用荧光定量PCR法,分别测定αENaC、βENaC、γENaC在各组织的相对表达水平。结果正常血压的Wistar大鼠ENaCs表达在主动脉弓和颈动脉窦区域相对定量较SHR组大鼠高,在颈动脉窦区域表现更明显。结论高血压状态下,ENaCs在压力感受器区域下调表达,提示压力敏感性离子通道在压力反射重调方面可能发挥着一定作用。     

四氧嘧啶致大鼠高血糖模型的实验研究

目的：探讨四氧嘧啶至Wistar大鼠高血糖模型的最佳实验条件。方法：根据不同条件对实验动物进行分组,使用四氧嘧啶腹腔注射导致动物产生高血糖,计算成模率和死亡率。结果：采用两次给药法,在给药剂量分别为120mg/kg(第1天）和100mg/kg（第2天）的条件下,随着体重的增高其成模率呈下降趋势。两次给药法的两组剂量（120mg/kg第1天,100mg/kg第2天;120mg/kg第1天,80mg/kg第2天）对成模率没有影响,剂量降低可减少死亡率。日照时间短,强度低,成模率明显降低,而且死亡率明显增高。结论：用四氧嘧啶制备糖尿病模型是一种经济可靠的实验方法。但实验条件要求较为苛刻。实验选取雄性Wistar大鼠,体重190-240g,在日照时间10h以上且阳光充足的条件下饲养。给药方式采取两步给药法,剂量为120mg/kg第1天,100mg/kg第2天,其成模率最高。     

正常Winstar大鼠多焦视网膜电图特点

目的了解正常Winstar大鼠多焦视网膜电图(mERG)特点,为进一步研究打下基础。方法正常雄性Winstar大鼠10只,在同一时间段行多焦视网膜电图检查,记录其多焦视网膜电图的结果。结果正常雄性Winstar大鼠多焦视网膜电图b波的反应密度分布较稳定,各环b波波幅值有差异性,各环b波波幅值之间有一定相关性。结论稳定、可靠的记录大鼠多焦视网膜电图,有着广泛的科研应用价值。     

大鼠带蒂胃壁瓣肠移植的组织学与电镜观察

将４０只大鼠带蒂胃壁瓣分别自体移植到十二指肠，空肠及结肠，于术后３，６，９，１２个月，分批处死动物进行观察。胃粘膜由胃内酸性环境进入肠道碱性环环境后，发生了广泛肠化生，化生组织内含有杯状细胞，柱状细胞及潘氏细胞，部分标本中有肠型隐形成。十二指肠和空肠移植的胃壁瓣粘膜显示碱性磷酸酶阳性肠化生。透射电镜和扫描镜观察可见杯状细胞和典型或非典型微绒毛。研究结果证实了胃粘膜肠上皮化生是一种微环境相关性变化，     

Role for the urinary bladder in pathogenesis of metabolic syndrome in Wistar rats

INTRODUCTION: Perfusion of rat urinary bladder with uric acid (UA) or 1-methyl uric acid (1-MUA) solution was reported to produce features of metabolic syndrome, viz. hyperglycaemia, hyperinsulinaemia, hypertriglyceridaemia and hypercholesterolaemia. The present study was carried out to confirm that UA or 1-MUA in the bladder can produce insulin resistance, and to demonstrate that an unknown humoral factor from the bladder is possibly involved in producing features of metabolic syndrome. METHODS: Wistar rats weighing 200-300 g were used. Two sets of protocols, perfusion study and cross-over study, were followed. For the perfusion study, urinary bladders were perfused with distilled water or solution of UA or 1-MUA, and serum levels of glucose and insulin and insulin resistance during perfusion were compared between groups. For the cross-over study, serum from distilled water or UA perfused rats (donors) was infused intravenously into rats (recipients), and serum levels of glucose, insulin, true triglyceride and total cholesterol and insulin resistance were compared. RESULTS: Perfusion of bladder with UA or 1-MUA solution resulted in an increase in serum levels of glucose and insulin, and insulin resistance, on comparison with distilled water perfused. Infusion of serum from donors perfused with UA resulted in hyperglycaemia, hyperinsulinaemia, hypertriglyceridaemia and hypercholesterolaemia and increase in insulin resistance in recipients when compared with recipients infused with serum from donors perfused with distilled water. CONCLUSION: The present study confirms that UA and 1-MUA in the bladder produce features of metabolic syndrome and could be the result of an unknown humoral factor released from the bladder mucosa.     

自发性高血压大鼠和Wistar大鼠脑动脉Cx45表达的差异

目的 探讨脑动脉细胞间缝隙连接在高血压病中的变化。方法 应用全细胞膜片钳、定量RT PCR和Western blot技术,比较自发性高血压(SH)大鼠(n=30)和Wistar大鼠(n=30)脑动脉上缝隙连接耦联力,以及连接蛋白45(Cx45)在mRNA和蛋白水平的表达。结果 ① 应用全细胞膜片钳技术发现,SH大鼠脑动脉平滑肌细胞膜电容和膜电导都明显高于正常Wistar大鼠(P<0.05),提示SH大鼠脑动脉平滑肌细胞间的缝隙连接耦联力增强。② 应用定量RT PCR技术发现,SH大鼠脑动脉Cx45 mRNA的表达升高(P<0.05)。③ 应用Western blot发现,SH大鼠脑动脉Cx45的蛋白表达升高(P<0.01)。结论 SH大鼠可能通过上调平滑肌细胞上Cx45的表达,增强脑动脉平滑肌细胞间缝隙连接通讯,保证血管的同步收缩。     

应激对Wistar大鼠牙周炎动物模型的影响

目的：建立合适的牙周炎动物模型,探讨应激与牙周炎之间的关系。方法：40只Wistar 大鼠用尼龙丝线结扎左上颌第二磨牙,随机分为应激组（给予限制性应激）和对照组。于第2、4、6、8和10天分批处死大鼠,检测应激指标血糖、促肾上腺皮质激素（ACTH）、皮质类固醇、肾上腺素含量,测量胸腺和脾脏重量与体重的相对比值。观察上颌第二磨牙根分叉处的组织学改变,测量根分叉区牙槽嵴高度与根分叉高度比值。结果：胸腺/体重、脾脏/体重、血糖、ACTH、皮质类固醇、肾上腺素在应激组与对照组间比较差异均有显著性（P<0.05或P<0.01）;应激组结扎区根分叉区牙槽嵴顶至根分叉距离与根分叉高度比在第8和10天显著低于对照组（P<0.05或P<0.01）。结论：Wistar大鼠适于建立应激牙周炎动物模型,限制性应激不会导致牙周炎的发生,但可以加重牙周组织炎症的破坏程度。     

甘草甜素对幼龄大鼠实验性肝纤维化疗效的研究

目的 观察甘草甜素抗幼龄大鼠实验性肝纤维化的效果,探讨甘草甜素对儿童肝纤维化治疗及预防的作用。方法 制备幼龄大鼠实验性肝纤维化模型,用甘草甜素治疗,同步预防,观察幼龄大鼠一般情况、肝组织形态、光镜下病理变化。结果 甘草甜素治疗组在幼龄大鼠一般情况和光镜下病理学分级中,明显优于同步预防组和肝纤维化对照组,而同步预防组又优于肝纤维化对照组,且疗程越长,效果越明显。结论 甘草甜素对幼龄大鼠肝纤维化有明显治疗及预防作用。     

Acute and subchronic toxicity of hydroxylammonium nitrate in Wistar rats

Hydroxylammonium nitrate （HAN） is a major constituent in a class of liquid monopropellants and is extensively used in nuclear industry and space propulsion. Previous toxicological studies have focused on oral, inhalation and dermal routes of exposure to HAN-based propellant blends. In this study, acute and subchronic toxicity of HAN in Wistar rats by intraperitoneal injections were evaluated. In this acute study, doses of HAN at 115, 125, 135, 147, 160 or 174 mg/kg were administered. No adverse effects were observed during a 14-day period and at gross histopathological examination. In the subchronic study, HAN at 7, 14 or 28 mg/kg were administered for 13 weeks. The treatment with HAN caused significant changes in the weight of spleen, in the level of hematological parameters, total bilirubin, direct bilirubin, uric acid and carbondioxidecombining power and histopathological damages of the lung, liver, spleen and kidney. Overall, the study suggests that 13-week HAN treatment caused abnormal hematological changes and tissue lesions, and the risk of toxicity to mammals is not negligible.