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除草剂敌草快(Diquat)所致的大鼠胎儿动脉管收缩与血管紧张素及其受体的关系 总被引：1，自引：0，他引：1
为研究除草剂敌草快（Diquat）对胎儿动脉管的毒性作用机理，进行了以下3个试验：（1）取妊娠21d大鼠20只，随机分成5组，每组4只，于不同时间皮下注射敌草快7mg／kg，对照组注射等量生理盐水。取出胎儿，冷冻后，观察动脉管收缩情况。（2）取妊娠21d大鼠16只，随机分成4组，每组4只。试验1组母体皮下注射敌草快7mg／kg，2、3组通过子宫壁给胎儿分别注射D．05mL生理盐水和0．05mL（0．05mg）非选择性血管紧张素（ET）受体ETA／ETB拮抗药TAK-044后，再母体皮下注射敌草快7mg／kg，取出胎儿，观察动脉管收缩情况。（3）取妊娠21d大鼠16只，随机分成4组，每组4只。试验1组母体皮下注射敌草快7mg／kg，2、3组通过子宫壁给胎儿分别注射0．05mL生理盐水和0．05mL（0．02mg）选择性ETA受体拮抗药BQ-123后，再母体皮下注射敌草快7mg／kg，取出胎儿，观察动脉管收缩情况。结果表明，敌草快对妊娠末期胎儿动脉管有毒性作用，胎儿注射TAK-044和BQ-123都不引起动脉管收缩。由此可见，敌草快所致胎儿动脉管收缩与ET有关，且有ETA受体作为媒介参与。 相似文献
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本文研究了敌草快和肾上腺皮质激素对胎鼠动脉管的收缩作用。取妊娠19、20、21 d的大鼠,各随机分成2组。试验组皮下注射7 mg/kg敌草快,观察胎鼠动脉管收缩情况;取妊娠19 d大鼠,随机分成4组,试验1组未切除肾上腺,2、3组切除肾上腺。1、3组皮下注射7 mg/kg敌草快,第2组和对照组注射生理盐水,观察胎鼠动脉管收缩情况,并且测定母鼠血浆中肾上腺皮质激素的浓度;取妊娠19、20、21 d大鼠,各随机分成2组,试验组皮下注射40 mg/kg肾上腺皮质激素,观察胎鼠动脉管收缩情况,另用80 mg/kg肾上腺皮质激素,重复上述操作。结果表明:敌草快和肾上腺皮质激素对妊娠末期胎鼠动脉管具有收缩作用,且引起收缩的临界期均在胎龄19￣20 d。 相似文献
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研究敌草快所致的大鼠胎儿动脉管收缩与肾上腺皮质激素及其受体的关系。①取妊娠19d大鼠20只，随机分为4组。试验1组未切除肾上腺，2、3组切除两侧肾上腺。1、3组皮下注射7mg／kg敌草使．2组和对照组皮下注射等量生理盐水。取出胎儿，冷冻后观察动脉管收缩情况。②在①里取出胎儿后，从各组母体的腹大动脉中采取血液，测定肾上腺皮质激素浓度。③在①里取出胎儿后，切断头部，收’集血液，测定肾上腺皮质激素的浓度。④取妊娠19、20、21d大鼠各20只，随机分成2组。试验组、对照组分别皮下注射40mg／kg肾上腺皮质激素和等量生理盐水，取出胎儿，冷冻后观察动脉管收缩情况。另用80mg／kg肾上腺皮质激素，重复上述操作。⑤取妊娠21d大鼠20只，收集120只胎儿动脉管，大动脉和母体肝脏，Western blotting法定量其组织液中蛋白质，并与标准肾上腺皮质激素受体蛋白（97000）对照比较。另取妊娠19、20、21d大鼠各20只，收集各自胎儿心脏及心血管系统，通过免疫组织学方法，观察胎儿动脉菅内皮中肾上腺皮质激素受体的分布情况。结果表明，敌草快能促进妊娠末期母鼠分泌大量肾上腺皮质激素；注射肾上腺皮质激素的胎儿动脉管内径明显小于对照组，且引起收缩的临界期为胎龄19～20d；妊娠20、21d胎儿动脉管内皮细胞中存在肾上腺皮质激素受体。由此可见，敌草快能促进肾上腺皮质激素的释放，肾上腺皮质激素对胎儿动脉管具有收缩作用。 相似文献
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胆酸负荷对妊娠大鼠母体及其胎儿IGF-2和营养代谢物水平的影响 总被引：2，自引：0，他引：2
30只成年妊娠SD大鼠随机分为A，B，C3组，在妊娠13－20d给A组和B组大鼠每天分别腹腔注射2.9mg/kg和5.5mg/kg胆酸，C组同步注射等量生理盐水。妊娠21d时宰杀母鼠，剖腹取胎，测定胎儿体重，胚胎成活率。并采集母体和胎儿血样，测定IGF－2、胰岛素和代谢物水平。结果表明，低剂量胆酸注射导致胎儿成活率降低7．02％，胎儿血浆IGF－2升高及乳酸和总蛋白水平降低，母体血浆IGF－2和胰岛素水平降低。较大剂量胆酸注射使胎儿成活率和体重分别下降38．27％和7．33％，血浆IGF－2、胰岛素和总蛋白水平下降。结果提示长期胆酸负荷对胎儿生长发育产生严重影响，胎儿死亡率增加及生长迟缓与IGF－2、胰岛素水平降低有关。 相似文献
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精氨酸对妊娠后期鄂尔多斯细毛羊胎儿生长发育的影响研究 《畜牧与饲料科学》2016,37(4):33-33
旨在通过对鄂尔多斯细毛羊母羊颈静脉灌注L-精氨酸,研究其对鄂尔多斯细毛羊母羊妊娠后期（90-140d）胎儿生长与发育的影响。试验选择22只母羊,在90 d开始灌注115μmol L-Arg-HCl/kg体重（Arg1组）、155μmol L-Arg-HCl/kg体重（Arg2组）和生理盐水（对照组）,3次/d。妊娠第115天和第140天,进行实验母羊孕体检查,并记录胎儿体重、器官重量和体尺长度,收集母体及胎儿血浆测定血浆氨基酸浓度。结果表明,母羊妊娠第140天,Arg2组较Arg1组和对照组显著增加了胎儿心脏和肝脏重量（P〈0.05）。母羊妊娠第115天和第140天,灌注L-精氨酸显著增加母体血浆精氨酸和鸟氨酸浓度（P≤0.01）,增加胎儿血浆生糖氨基酸（苏氨酸、甲硫氨酸、苯丙氨酸和赖氨酸）浓度（P≤0.05）。 相似文献
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3-甲基-4-硝基酚对大鼠睾丸组织的损伤作用 总被引：1，自引：0，他引：1
为从病理学角度探讨3-甲基-4-硝基酚(PNMC)的生殖毒性,采用24只SPF雄性SD大鼠随机分为4组,染毒组分为100 mg/kg体重、10 mg/kg体重和1 mg/kg体重三组,连续5 d皮下注射,对照组皮下注射等量的溶剂(PBS+0.05%tween80)。最后一次染毒后24 h,无痛处死大鼠,称取睾丸湿重并计算其指数。将已固定的睾丸组织进行石蜡切片,采用H.E和免疫组化染色的方法观察PNMC对大鼠睾丸的病理损伤及其对凋亡相关蛋白Bcl-2和Bax表达的影响。结果显示各个染毒组与对照组相比较,睾丸大体湿重和睾丸指数明显下降(P0.05或P0.01);H.E染色结果显示各试验组睾丸曲细精管生精细胞均有不同程度的空泡变性兼或坏死;免疫组织化学染色观察发现:各实验组睾丸中Bax蛋白表达量显著高于对照组(P0.01),而Bc1-2蛋白表达量却明显低于对照组(P0.01),Bc1-2/Bax也显著低于对照组(P0.01)。研究结果表明,PNMC不仅可引起雄性大鼠睾丸曲细精管生精细胞变性、坏死,还可促进生殖细胞的大量凋亡。 相似文献
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通过小鼠急性毒性试验和大鼠亚慢性毒性试验评价防制奶牛隐性乳房炎中药"乳宁散"的安全性。将"乳宁散"制备成相当于原药材1.0 g/mL的水煎提取浓缩液,选取50只小鼠,随机分为5组,以5000、7500、10000、15000 mg/kg体重的剂量1次灌胃给药,观察中毒症状,记录死亡数和计算半数致死量(LD50);另取40只小鼠,随机分为2组,给药组以最大浓度(1.0 g/mL)、最大容积(0.04 mL/g)1次灌胃受试药物,对照组用等体积生理盐水,给药后连续观察7 d,测定最大给药量;再取80只大鼠,随机分成药物处理高、中、低剂量组和对照组,药物组按大鼠体重3000、1500和750 mg/kg剂量灌胃给药,连续30 d,对照组用生理盐水,检测大鼠体重、血常规指标、血液生化指标、脏器系数及组织病理变化情况。结果表明,急性毒性试验各剂量组均无小鼠死亡,无法计算LD50,经口给药的最大剂量为40.0 g/kg体重,表明该产品实际无毒;亚慢性毒性试验中,药物处理组大鼠体增重、血常规、血液生化指标和脏器系数与对照组相比无显著差异(P>0.05),组织病理学观察实质器官无异常病变。提示,临床合理使用中药"乳宁散"不会对靶动物产生毒性作用。 相似文献
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Takizawa T Horikoshi E Shen MH Masaoka T Takagi H Yamamoto M Kasai K Arishima K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(5):505-509
We studied the effects of TAK-044, a nonselective endothelin (ET) receptor antagonist, on the indomethacin- or methylene blue-induced constriction of the ductus arteriosus (DA) in rats and compared them with the effects on spontaneous DA constriction. Injection of TAK-044 into 21-day-old fetuses in utero was performed through the uterine wall of laparotomized mother rats under light ether anesthesia. The fetuses were autopsied 3 hr after treatment with TAK-044 (10 mg/kg) in utero and simultaneous administration to the laparotomized mother rats of indomethacin (3 mg/kg, p.o.) or methylene blue (100 mg/kg, i.p.). In the second experiment, pregnant rats were decapitated on day 21 of gestation to obtain newborn rats by cesarean delivery. Newborn rats which were given TAK-044 (2, 10 mg/kg) immediately after or 1 hr before cesarean delivery were autopsied at various times after birth. In both experiments, pups were rapidly frozen in an acetone-dry ice mixture at autopsy to evaluate the DA constriction by the whole-body freezing and shaving method. TAK-044 injection into the fetus 3 hr before autopsy completely inhibited the DA constriction induced by maternal treatment with indomethacin or methylene blue. TAK-044 caused dose-dependent inhibition of the spontaneous closure of the DA after birth. The inhibitory effect was more pronounced in pups which were given TAK-044 in utero 1 hr before birth; however, the inhibitory effect was incomplete in newborn pups. These results, together with the previous finding that BQ-123, an ETA-specific receptor antagonist, inhibits the ductal constriction induced by oxygen in vitro [Coceani et al., 1992], indicate that the ETA receptor plays a significant role in the indomethacin- or methylene blue-induced DA constriction as well as in the spontaneous DA constriction after birth, and also indicate that the inhibition of ETA receptor by TAK-044 was more easily achieved in fetuses than in neonates. 相似文献
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通过注射链脲佐菌素(STZ)制作大鼠1型糖尿病模型,观察大鼠品系、给药剂量、给药次数对大鼠成模率、死亡率的影响,同时研究利用口服葡萄糖耐量试验(OGTT)判断大鼠糖尿病成模率的意义。随机取16只SD大鼠设置正常对照组。试验一:Wistar大鼠随机分为中剂量组(55 mg/kg,n=12)和高剂量组(65 mg/kg,n=12);试验二:SD大鼠一次性腹腔注射STZ(55 mg/kg,n=12),与1中的Wistar大鼠作对比;试验三:SD大鼠随机分为一次给药组(n=16)和两次给药组(n=16),注射剂量均为55 mg/kg,观察期间进行OGTT。结果表明,Wistar大鼠成模率和死亡率均高于SD大鼠;采用SD大鼠、中剂量给药和两次给药的方式可提高成模率,并降低死亡率;在有明确胰岛病理改变的模型组大鼠,其OGTT异常阳性率显著高于空腹血糖异常阳性率。用STZ诱导糖尿病模型是一种稳定可靠的方法。 相似文献
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The purpose of this publication was to examine the effects of a wide variation of dietary vitamin B1 supply (0-12,000 mg vitamin B1 per kg diet) to gravid and non gravid rats on their vitamin B1 content in liver, brain and muscle. The experiment was designed with 176 (2 x 11 x 8) female Sprague-Dawley-rats. Additionally, the organs and tissues were tested as criteria for requirement recommendations. The animals were sacrificed on the 20th day of gravidity of the pregnant rats. Before gravidity the vitamin-B1-contents were 4.7 micrograms/g liver, 2.5 micrograms/g brain and 1.5 micrograms/g muscle. At the end of the experiment the gravid rats had a 19 per cent higher liver content than the non gravids. With a dietary supply of 8-10 ppm vitamin B1 the liver content plateaued until about 120 ppm. Vitamin B1 concentration in brain was about 2 micrograms/g and gravidity was of no effect. Vitamin B1 concentration in muscle was significantly influenced by both factors and saturation was reached at 1.3 and 1.7 micrograms/g muscle. These data showed that the response of the liver to dietary supply was the most sensitive and should therefore be considered in requirements. The requirement for non gravid animals is therefore 4 mg vitamin B1 per kg diet at minimum, gravid animals should be supplied by 7 mg per kg diet. 相似文献
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Cisplatin is a chemotherapeutic agent widely used in treatment of several cancers. It is documented as a major cause of clinical nephrotoxicity and hepatotoxicity. The purpose of this study was to investigate the involvement of oxidative stress in the pathogenesis of cisplatin-induced liver and kidney injury. Wistar rats were divided into four groups. Group 1 (control) was intraperitoneally (IP) injected with a single dose of 0.85% normal saline. Groups 2, 3 and 4 were IP injected with single doses of cisplatin at 10, 25 and 50 mg/kg body weight (BW), respectively. At 24, 48, 72, 96 and 120 h after injection, BW, levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine, malondialdehyde (MDA), and activity of superoxide dismutase (SOD) and histology of the liver and kidney were evaluated. Cisplatin caused a reduction in BW of rats in groups 2, 3 and 4 at all post injection intervals. The levels of serum ALT, AST, BUN and creatinine and MDA of the kidney and liver were markedly increased especially at 48 and 72 h, whereas the activity of SOD was decreased after cisplatin injection. Liver sections revealed moderate to severe congestion with dilation of the hepatic artery, portal vein and bile duct and disorganization of hepatic cords at 50 mg/kg of cisplatin. Kidney sections illustrated mild to moderate tubular necrosis at 25 and 50 mg/kg of cisplatin. Therefore, oxidative stress was implicated in the pathogenesis of liver and kidney injury causing biochemical and histological alterations. 相似文献
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OBJECTIVE: To compare the effect of pre- versus post-anaesthetic intramuscular (IM) buprenorphine on intermittent intravenous (IV) propofol anaesthesia in rats. ANIMALS: Twenty healthy, adult, female, ex-breeder Sprague-Dawley rats within the mass range 274-379 g. MATERIALS AND METHODS: Animals were randomly allocated to one of two groups. Group 1 (n = 10) received 9 mug buprenorphine (IM) at the start and group 2 (n = 10) received the same dose buprenorphine at the end of anaesthesia. Five animals from each group (randomly selected) received a standardized 40-minute surgical procedure (procedure 1), the remaining half, a standardized 60-minute surgical procedure (procedure 2). Induction of anaesthesia with 4% isoflurane carried in oxygen was immediately followed by IV propofol (3 mg) and intraperitoneal diazepam (500 microg). Anaesthesia was maintained using periodic IV propofol (500 microg) injected through an indwelling tail vein cannula, by an operator ignorant of the buprenorphine status. One hour after recovery from anaesthesia, the animals' level of awareness were scored by an observer ignorant of both the buprenorphine status and the total propofol dose administered. RESULTS: Buprenorphine administration at the start of anaesthesia versus administration at the end resulted in a significant reduction in the total per-kilogram requirement for propofol from a mean of 24 mg kg(-1) (+/-2.5 mg kg(-1), n = 5) to 5.5 mg kg(-1) (+/-1.1 mg kg(-1), n = 5) for procedure 1, and from a mean of 30 mg kg(-1) (+/-1.2 mg(-1), n = 5) to 16 mg kg(-1) (+/-1.0 mg kg(-1), n = 5) in procedure 2. Animals receiving buprenorphine at the start of anaesthesia demonstrated a higher level of awareness 1 hour after cessation of anaesthesia. No adverse effects were evident in either group 24 hours after recovery. CONCLUSIONS: Buprenorphine administration at the start of periodic IV propofol anaesthesia in rats resulted in a significant reduction in the total propofol requirement and significantly improved the 1-hour post-anaesthesia recovery score. Clinical relevance Besides the ethical advantage of pre-emptive analgesia, pre-anaesthetic medication with buprenorphine in rats significantly reduces the total propofol requirements for surgical anaesthesia and in this study was found to be a safe and effective method of anaesthesia. 相似文献
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三聚氰胺对雌性Wistar大鼠的慢性毒性研究 总被引：1，自引：0，他引：1
三聚氰胺（melamine,MA）对小鼠的经口LD50为4550mg/（kg.bw）,急性毒性属于低毒物质。为证实和客观评价其慢性毒性,以每千克饲料500、1000和2000mgMA/kg饲料的剂量对6周龄雌性Wistar大鼠进行了6个月慢性毒性试验。结果表明,各剂量组雌性Wistar大鼠肾、肝和膀胱均有不同程度地功能异常和器质性病变;血液ALT、AST、CRE和UA等生化指标均有不同程度地升高,肾、肝和膀胱黏膜均有不同程度地病理变化或损伤;每千克饲料2000mgMA/kg饲料的剂量能够抑制大鼠生长和采食,肾病理变化显著,出现结石;染毒组大鼠脾脏、骨髓等未见病变;MA对大鼠的最大无作用剂量应小于（35.7±15.4）mg/（kg.bw.d）。 相似文献
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A study involving 60 light-horse mares was conducted both to evaluate the response of mares to injectable progester- one or altrenogest and to determine ifestradiol in combination with either progestogen provided any added benefit. Treatments were initiated at either early estrus, late estrus, early diestrus, mid-diestrus or late diestrus in order to assess the effect of stage of cycle at onset of treatment. Within each of these stages of the cycle, mares were randomly assigned to 1 of 4 treatments: 150 mg progesterone injected i.m. (P); 150 mg progesterone + 10 mg estradio11713 injected i.m. (P+); .044 mg altrenogest per kg body weight orally (A); and .044 mg per kg body weight orally plus 10 mg estradiol 1713 i.m. (A+). All treatments were given daily for 7 days with 10 mg PGFaCt given on day 7 to all mares. The number of mares ovulating by day 14 after treatment (N=15/group) was 13, 7,11 and 8 forA, A+, P and P+, respectively. The response of mares to progesterone and altrenogest was similar. Fewer (Pì0.05) mares given combined steroid treatments ovulated within 14 days (15 of 30) than those given progestogen treatments. Stage of cycle had no affect (Pì0.05) on response of mares ovulating within 14 days or after 14 days of treatment. Mares that ovulated within 14 days of treatment had larger foUieles after progestogen treatment than those not ovulating by 14 days. 相似文献
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Thyrotrophin was injected i/p at 2 I.U. daily simultaneously with oral administration of Turisynchron at 100 mg/kg or Suisynchron at 125 mg/kg daily for five days to Wistar rats. The uptake of radio-iodine by the thyroid was reduced, and there were slight changes in thyroid structure. Suisynchron produced a milder inhibition of thyroid regulatory mechanisms than Turisynchron. 相似文献