镉对雌性大鼠排卵功能的影响

选动情间期SD种雌性大鼠,分别皮下注射5和10mg/kg CdC12及生理盐水1.0ml/kg。染毒后第6天用戊巴比妥麻醉,再静脉注射0.5和2.0μg/kg LHRH。结果表明,LHRH能使垂体和血清中LH含量升高。另一试验,动情间期SD大鼠,皮下注射10mg/kg CdCl_2后第6天,注射LHRH后,血清LH和孕酮水平明显升高,能部分恢复排卵功能。实验结果提示,Cd~(2+)中止排卵过程似乎在于使垂体释放LH减少,进而使LH对卵巢黄体功能的支持减退,这可能是Cd~(2+)阻断孕酮作用的途径之一。     

镉对大鼠卵巢性激素分泌功能的影响

目的研究镉对卵巢性激素分泌功能的影响，探讨镉的雌性性腺毒性及其机制。方法成年雌性大鼠分为4组；对照组9只，3个染毒组每组10只，于皮下注射氯化镉（含Cd^2＋0、0．25、0．5、1．0mg／KS）进行亚慢性染毒（1次／d，每周5d，连续30d），染毒结束时取卵巢进行全卵巢培养，采用放射免疫法测定雌二醇（E2）和孕酮（P）变化；按正交表L1。（44）设计取正常成年大鼠卵巢进行全卵巢培养，观察加入不同剂量CdCl2对取自动情周期不同阶段的卵巢分泌E2和P的影响，用放射免疫法测定。结果（1）体内实验提示：高剂量组E2和P水平（分别为1．3836pg／ml和5．2857ng／m1）显著降低，与对照组比较（分别为3．8976pg／ml和9．1583ng／ml），具有显著性（P〈0．05）；（2）体外实验：CdCl2和动情周期不同阶段对卵巢分泌E2和P有明显影响，对P的分泌存在交互影响，有显著性（P〈0．05）。结论在该实验条件下，镉的内分泌干扰作用可表现为抑制大鼠卵巢分泌E2和P；镉对卵巢性激素分泌作用的直接损害作用可能是其重要机制之     

胸腺因子D对老龄大鼠垂体-性腺轴内分泌激素的影响

目的　探讨胸腺因子 D对垂体 -性腺轴内分泌衰老的延缓作用。 方法 　雌、雄 2 1月老龄 SD大鼠各随机分成两组 ,一组隔日背部皮下注射胸腺因子 D2 mg· kg- 1 ,另一组及 6月青龄雌、雄对照注射等量生理盐水 ,连续处理 3个月后 ,用放射免疫法测定腺垂体组织、血清 FSF、L H和血清 E2 、T。结果 　与雄性青龄对照组相比 ,雄性老年血清 L H升高 ,血清 T和 E2 下降 ,给药后 ,这些老年性改变可部分得到改善 ,而腺垂体组织FSH和血清 FSH、L H、E2 、T在各雌性大鼠间无差异。结论 　胸腺因子 D可逆转老龄雄性大鼠垂体 -性腺轴内分泌激素的老龄性改变 ,从而延缓衰老     

促性腺激素用药前垂体降调节方案的回顾性分析

<正>近年来,辅助生殖技术在我国迅速发展,体外受精-胚胎移植(IVF-ET)周期常规应用促性腺激素释放激素激动剂(GnRH-a)联合促性腺激素(Gn)进行控制性超排卵。在控制性超排卵过程中运用GnRH-a长方案对垂体进行降调节,可抑制内源性促黄体生成素(LH)峰,避免卵泡黄素化,控制排卵时间,获得较高质量卵子,提高妊娠率。本文对我科2006     

卵巢低反应预处理后对IVF-ET结局的影响

目的 探讨在超排卵前补佳乐人工周期处理3个周期后对卵巢反应不良患者IVF-ET结局的影响.方法 选择2005年1月～2006年12月在我中心接受IVF-ET或ICSI治疗中预测将出现卵巢低反应的患者,21例设为研究组,在超排卵前给予补佳乐行人工周期3个周期;22例作为对照组,分析两组超排卵前不孕原因、不孕时间、基础内分泌以及超排卵时所用Gn天数、Gn支数、获卵数、受精数、优质胚胎数、妊娠率、早期流产率.结果 两组在不孕原因、不孕时间、基础内分泌无统计学差异性(P＞0.05);两组Gn天数、Gn支数、获卵数、受精数和优胚数亦无统计学差异性(P＞0.05),研究组妊娠率高于对照组,早期流产率低于对照组(P＜0.05).结论 补佳乐预处理后,可以提高卵巢反应不良患者的妊娠率,降低流产率.     

内外源性促性腺激素对卵巢源肾素-血管紧张素系统的影响

目的 测定正常月经周期围排卵期前后以及促超排卵患者于人绒毛膜促性腺激素（HCG）注射前后血中肾素（PRA）活性和血管紧张素Ⅱ（PANGⅡ）浓度变化,探讨内外源性促性腺激素对卵巢源肾素-血管紧张素系统的影响.方法 正常月经周期30例、促超排卵周期妇女20例.分别于正常周期的卵泡期、尿LH阳性日和阳性后24 h,促排卵周期于HCG注射日、取卵日、移植日采血,测定PRA活性和PANGⅡ浓度.结果 PRA、PANGⅡ于尿LH阳性日和阳性后24 h较卵泡期明显升高,取卵日和移植日明显高于HCG注射日水平.结论 内外源性促性腺激素均可以激活卵巢源肾素-血管紧张素系统.     

八珍益母丸对更年期雌性大鼠卵巢、子宫及激素的影响

目的探讨八珍益母丸对更年期雌性大鼠卵巢、子宫及激素的影响。方法建立更年期大鼠模型,观察口服八珍益母丸后更年期雌性大鼠卵巢、子宫指数及血清雌激素(E2)、促黄体生成激素(LH)、促卵泡激素(FSH)、孕激素(P)4项激素水平的变化。结果八珍益母丸组可显著提高子宫、血清E2和P 2项激素水平。结论八珍益母丸具有增加更年期雌性大鼠子宫指数、血清E2和P激素水平的作用。     

Toxicity of 2-methyl-4-chlorophenoxy acetic acid alone and in combination with cyhalofop-butyl to Cyprinus carpio embryos

Herbicides may pose considerable danger to non-target aquatic organisms and further threaten human health. The present investigation was aimed to assess the effects of 2-methyl-4-chlorophenoxy acetic acid (MCPA-Na) on Cyprinus carpio embryos. Embryos were exposed to six concentrations of MCPA-Na (0, 52, 54, 56, 58 and 60 mg/L) for 96 h. A series of symptoms were observed in developmental embryos during MCPA-Na exposure, including increased death, hatching inhibited and morphological deformities. Further, MCPA-Na exposure leading to a series of morphological changes (pericardial edema, tail deformation, and spine deformation) in embryos, which were consistent with modifications in the associated genes. In this work, we also investigated the joint toxicity of herbicides (MCPA-Na and cyhalofop-butyl) commonly used in paddy fields on carp embryos, using the 96 h-LC₅₀ of herbicides (59.784 mg/L MCPA-Na and 1.472 mg/L cyhalofop-butyl) and confirmed that a synergistic effect existing in the binary mixtures.     

Cadmium-induced changes in Per 1 and Per 2 gene expression in rat hypothalamus and anterior pituitary: effect of melatonin

Chronic cadmium (Cd) administration affects the circadian release of pituitary hormones in rats. To assess whether Cd modifies expression of two major clock genes, period (Per) 1 and Per 2, in the hypothalamic-pituitary unit and to what extent the changes could be prevented by melatonin, rats were exposed to CdCl(2) (5ppm in drinking water) with or without melatonin (3 microg/mL drinking water) for 1 month and were killed at two time intervals, i.e. a the beginning of the rest span (09:00h) and at the middle of the activity span (01:00h). Hypothalamic and pituitary mRNA levels encoding Per 1 and Per 2 were measured by real-time PCR analysis. Cd treatment decreased expression of hypothalamic Per 1 gene at both time intervals, of hypothalamic Per 2 gene at 01:00h, and of adenohypophysial Per 1 and Per 2 genes at 09:00h. Melatonin administration counteracted most of the effects of Cd and augmented hypothalamic Per 2, and adenohypophysial Per 1 and Per 2 gene expression. The results indicate that Cd administered chronically in the drinking water to rats affected expression of clock genes in the hypothalamic-pituitary unit, an effect prevented by melatonin.     

Pharmacokinetics of biosynthetic and pituitary human growth hormones in rats

The pharmacokinetics of biosynthetic and pituitary human growth hormones (B-hGH and P-hGH) was compared in rats. Normal and hypophysectomized male and female rats were subcutaneously and intramuscularly injected with 100 micrograms/kg B-hGH and P-hGH and intravenously with 60 micrograms/kg B-hGH and P-hGH. A statistically significantly smaller distribution volume and a slower metabolic clearance rate (MCR) was found for B-hGH compared to P-hGH. A statistically significantly smaller distribution volume and MCR was found for hypophysectomized rats compared to normal rats. The plasma half lives were estimated to be about 3-7 min. (alpha 1/2) and 29 min. (beta 1/2). The plasma levels of hGH were higher after subcutaneous compared to intramuscular administration. The data imply that an extensive local degradation took place at the subcutaneous and intramuscular injection sites. Comparative tissue distribution studies were performed with radioiodinated B-hGH and P-hGH. No differences were observed between the growth hormones. It was found that most of the labelled TCA precipitable material was cleared through the liver. The females cleared relatively more through the liver than the males, while the males cleared relatively more through the kidneys.     

伽利可胶丸抗炎和急性毒性试验研究

本文应用伽利可胶丸０．５ｍｌ／ｋｇ、０．２５ｍｌ／ｋｇ给小鼠ｉｇ给药,可明显减轻巴豆油引起小鼠耳廓肿胀,说明伽利可胶丸对急性浅层组织的炎症有较好的抑制作用。急性毒性试验,测得小鼠ｉｇ最大耐受量为４０ｍｌ／ｋｇ,相当临床日用量的１６６６倍（临床日用量是０．０２４ｍｌ／ｋｇ）小鼠腹腔注射（ｉｐ）ＬＤ５０为２１．３２０６ｍｌ／ｋｇ,相当于临床日用量的８８７．５倍,说明该药毒性极低。     

Inhibitory effect of nicotinamide to paraquat toxicity and the reaction site on complex I

The inhibitory effect and mechanism of action of nicotinamide to paraquat toxicity were studied in male Sprague-Dawley rats. Proteins of submitochondrial particles (SMP), especially of mol. wt. 25–30 kDa, in rat lungs were destroyed by paraquat radicals, and aggregated protein bands ∼100 kDa were observed by polyacrylamide electrophoresis. The competitive inhibition effects were observed of nicotinamide on NADH oxidation by paraquat via SMP in rat lungs and the K _i was 9.3 mM. The inhibitory effects of nicotinamide on lipid peroxidation by paraquat with rat lung and liver SMP were verified. The times of occurrence of dyspnea and death in rats after paraquat exposure were delayed by nicotinamide administration. The activity of NADH: ubiquinone reaction of NADH:ubiquinone oxidoreductase (complex I) in rat lung was reduced 24 h after paraquat exposure, and was protected by nicotinamide. The activity of NADH:ferricyanide reaction of complex I was, however, reduced by administration not only of paraquat but also nicotinamide. These results imply that nicotinamide is inhibitory to paraquat toxicity. Nicotinamide, paraquat, and ferricyanide may react at overlapping sites on complex I. Received: 14 April 1997 / Accepted: 13 May 1997     

Evaluation of effects of prenatal exposure to the cyanide and thiocyanate in wistar rats

A study was performed at term and at weaning to verify the toxic effects of the prenatal exposure to potassium cyanide (KCN) and potassium thiocyanate (KSCN) in pregnant Wistar rats. Females received daily in drinking water the doses: 1, 3 and 30 mg KCN/kg or 0.8, 2.4 and 24 mg KSCN/kg from GD 6 to GD 20 and were euthanized on GD 20 (trial A) or one day after weaning (trial B). Skeletal and visceral analyses of the fetuses (trial A) were performed and samples of blood and different organs, from both dams (trials A and B) and weaned pups (trial B), were collected in order to perform the biochemical evaluation and histopathology. Results showed high thiocyanate levels in dams of the different experimental groups from both trials. The intensity of the histological lesions observed in dams of trial B was similar to that of trial A, except those lesions found in the pancreas. The histopathological study of this organ revealed loss of cells in the Islets of Langerhans from dams of trial A which received the highest dose of cyanide (CN). There was an increase in the number of biliary ducts in animals treated with the highest doses of both thiocyanate and cyanide. The histopathological study of the spleen and the lungs of experimental and control groups did not reveal any significant alteration. In relation to fetuses (trial A), the visceral and skeletal evaluations did not reveal any significant malformation; on the other hand, pups from trial B showed some histological alterations similar to those observed in their dams. It is concluded that the cyanide and/or thiocyanate promoted toxic effects in the fetuses some of which could also be observed at weaning.