α-MSH对EGTA性发热效应及脑腹中隔AVP含量的影响

目的和方法：观察脑腹中隔精氨酸加压素（ＡＶＰ）在α－黑素细胞刺激素（α－ＭＳＨ）解热机制中的作用；用放射免疫法测定ＡＶＰ含量。结果：ＥＧＴＡ引起明显的发热反应（Ｐ＜０．０１），同时降低脑腹中隔ＡＶＰ含量（Ｐ＜０．０５）。α－ＭＳＨ可抑制ＥＧＴＡ性发热反应（Ｐ＜０．０１），并增加脑腹中隔ＡＶＰ含量（Ｐ＜０．０５）；而对正常家兔体温及脑腹中隔ＡＶＰ含量无影响（Ｐ＞０．０５）。结论：α－ＭＳＨ对ＥＧＴＡ的解热作用可能部分是通过增加脑腹中隔ＡＶＰ的释放而实现的。在限制发热的过程中，内生解热物α－ＭＳＨ与ＡＶＰ可能具有协同作用。     

牛磺酸降温时腹中隔,下丘脑精氨酸加压素含量的变化

目的：探讨牛磺酸的降温机制。方法：建立家兔ＥＴ发热模型，观察侧脑室灌注牛磺酸对家兔体温的影响和用放射免疫分析法检测腹中隔、下丘脑区ＡＶＰ含量的变化。结果：牛磺酸具有降低家兔ＥＴ发热和正常体温的作用，伴有腹中隔ＡＶＰ含量明显增加（Ｐ＜００１）；而下丘脑ＡＶＰ含量变化不明显（Ｐ＞００５）。结论：牛磺酸的降温作用可能与腹中隔ＡＶＰ的含量增加有关     

α—MSH对内毒素性发热效应及下丘脑cAMP含量的影响

目的：观察α－黑素细胞刺激素（α－ＭＳＨ）对内毒素（ＥＴ）发热效应及下丘脑组织环一磷酸腺苷（ｃＡＭＰ）含量的影响。结果：α－ＭＳＨ能明显抑制ＥＴ引起的体温升高（Ｐ＜００５），同时降低ＥＴ引起的下丘脑组织ｃＡＭＰ含量的升高（Ｐ＜００１）；而对正常家兔体温及下丘脑组织ｃＡＭＰ含量均无影响（Ｐ＞００５）。结论：α－ＭＳＨ抑制中枢发热介质ｃＡＭＰ的生成可能是降低ＥＴ发热效应的主要机制之一。从而证明发热时中枢神经不但存在正调节途径，也存在负调节途径，体温上升的水平是正调节和负调节相互作用的结果     

家兔EGTA性发热时脑腹中隔区AVP含量的变化

本研究采用新西兰家兔４８只，随机分成４组，分别观察向侧脑室灌注ＥＧＴＡ、ＥＧＴＡ＋ＣａＣｌ＿２或ＣａＣｌ＿２对体温和脑腹中隔区ＡＶＰ含量的影响。结果表明，侧脑室灌注ＥＧＴＡ，不仅引起结肠温度明显上升（Ｐ＜０．００１）．还引起腹中隔区ＡＶＰ含量明显降低（Ｐ＜０．０５）；灌注ＥＧＴＡ后立即灌注ＣａＣｌ＿２，抑制了结肠温度的升高并逆转了腹中隔ＡＶＰ含量的降低。体温反应指数与腹中隔区ＡＶＰ含量呈显著负相关（ｒ＝－０．８３７４，Ｐ＜０．０１）；单独灌注ＣａＣｌ＿２引起结肠温度下降和腹中隔ＡＶＰ含量明显增加（Ｐ＜０．０１），提示ＡＴＰ可能参与ＥＧＴＡ性发热的中枢调节机制，中枢Ｃａ￣（２＋）浓度或Ｎａ￣＋／Ｃａ￣（２＋）比值变化可能是调控发热时腹中隔区ＡＶＰ释放的一个重要因素。     

α-MSH拮抗剂对内毒素及肿瘤坏死因子性发热的作用

目的：观察α－黑素细胞刺激素（α－ＭＳＨ）拮抗剂［Ｄ－Ｔｒｐ７,Ａｌａ８,Ｄ－Ｐｈｅ１０］α－ＭＳＨ（６－１１）－ａｍｉｄｅ对家兔内毒素（ＥＴ）及肿瘤坏死因子（ＴＮＦ）性发热的影响。方法：侧脑室给药,ＳＴ－１型数字温度计测家兔的结肠温度。结果：（１）静脉注射ＥＴ,家兔体温呈典型的双相热;若事先侧脑室注射α－ＭＳＨ拮抗剂,则体温升高更明显,且热程明显延长,６ｈ体温反应指数（ＴＲＩ６）显著高于ＮＳ＋ＥＴ组（Ｐ＜０．０１）。（２）侧脑室注射ＴＮＦ－α引起体温明显升高;事先给予α－ＭＳＨ拮抗剂,则显著增强ＴＮＦ－α性发热效应（Ｐ＜０．０１）。而α－ＭＳＨ拮抗剂对正常体温无影响。结论：内源性解热物质α－ＭＳＨ在限制发热中发挥了重要作用。     

抗退饮对LP性发热家兔的下丘脑cAMP含量及脑腹中隔区AVP含量的影响

目的：探讨抗退饮解热机制。方法：建立家兔ＬＰ 发热模型,观察抗退饮灌胃对家兔体温的影响和用放射免疫分析法检测腹 中隔ＡＶＰ 含量及下丘脑ｃＡＭＰ 含量的变化。结果：（１） 抗退饮灌胃＋ 静注ＬＰ 组的△Ｔ 为（０－５１ ±０－２５） ℃、中隔区ＡＶＰ 含量为（１１－９５ ±４－５２） ｐｇｍｇ 、下丘脑ｃＡＭＰ 含量为（０－９１３ ±０－４５０） ｐｍｏｌｍｇ 、分别低于ＮＳ 灌胃＋ 静注ＬＰ 组的△Ｔ（１－１８ ±０－２７） ℃、中隔区ＡＶＰ 含量（２２－３７ ±３－５８） ｐｇｍｇ 、下丘脑ｃＡＭＰ 含量（１－５６２ ±０－３６０） ｐｍｏｌｍｇ（ Ｐ＜０－０１） 。（２） 中隔区ＡＶＰ 含量变化与体温变化呈明显正相关（ｒ ＝ ０－７８２ ,Ｐ＜ ０－０１） 。结论：抗退饮解热机制可能是通过抑制下丘脑ｃＡＭＰ 含量升高,同时促进腹中隔ＡＶＰ 释放两种途径发挥作用     

精氨酸加压素在内毒素热限形成中的作用

本文观察了家兔静脉注射不同剂量ＥＴ后中隔区，下丘脑组织及血浆中ＡＶＰ含量的变化。结果显示：在ＥＴ发热过程中，中隔区，下丘脑及血浆ＡＶＰ含量均显著增多（Ｐ＜０．０１）；ＥＴ发热达热限时，体温不再升高，中隔区与血浆ＡＶＰ含量也不再增多，且中隔区及血浆ＡＶＰ含量变化与体温变化呈明显正相关（ｒ＝０．９８４，０．０５＜Ｐ＜０．０１；ｒ＝０．９９４，Ｐ＜０．０１）；此时，下丘脑升高的ＡＶＰ含量开始下降（Ｐ０。     

肾上腺髓质素对内皮素促家兔气道平滑肌细胞增殖的抑制作用

在体外培养的家兔气道平滑肌细胞（ＡＳＭＣ）上，观察肾上腺髓质素（ＡＭ）对内皮素（ＥＴ）促ＡＳＭＣ增殖的影响及丝裂素活化蛋白激酶（ＭＡＰＫ）活性的变化。以探讨ＡＭ对ＡＳＭＣ增殖的调控。结果显示１０－８ｍｏｌ／ＬＥＴ－１显著刺激ＡＳＭＣ３Ｈ－ＴｄＲ参入及ＭＡＰＫ激活（Ｐ＜０．０１）。ＡＭ（１３－５２）呈剂量依赖地抑制ＥＴ－１的上述作用（Ｐ＜０．０５，Ｐ＜０．０１）。单独应用ＡＭ（１３－５２）对ＡＳＭＣ３Ｈ－ＴｄＲ参入及ＭＡＰＫ活性无明显影响。表明ＡＭ（１３－５２）可抑制ＡＳＭＣ对ＥＴ－１的增殖反应，其机理可能涉及ＭＡＰＫ活性的抑制。     

黑色素细胞刺激素对家兔血细胞生成内生致热原的影响

本文观察了黑色素细胞刺激素对体外培育的兔全血细胞产生内生致热原的影响。结果显示，Ⅲ组（“α－ＭＳＨ＋ＥＴ＋全血培养物”上清）的致热性明显低于Ⅱ组（“ＥＴ＋全血细胞培养物”上清）（０．０１＜Ｐ＜０．０５）；而α－ＭＳＨ单独与血细胞培养无降温物质产生；同时，相同剂量的α－ＭＳＨ对ＥＰ性发热无直接抑制作用。由此作者推论，α－ＭＳＨ能抑制ＥＴ诱生ＥＰ的产生，而这一作用可能是其抑制ＥＴ性发热的主要机制之一。     

白细胞介素—8对大鼠失血性休克血浆6—keto—PGF1α和TXB2含量的影响

目的和方法：本文观察重组人内皮细胞衍生的白细胞介素－８（ｒｈＥＤＩＬ－８）对大鼠晚期失血性休克血浆６－ｋｅｔｏ－ＰＧＦ１α和ＴＸＢ２含量的影响，并与平均动脉血压（ＭＡＢＰ）的变化作相关性分析。结果：晚期失血性休克血浆６－ｋｅｔｏ－ＰＧＦ１α含量明显降低（１０６７４±１２２６ｖｓ１５６８２±１１４２）ｎｇ／Ｌ，Ｐ＜００１，ＴＸＢ２含量明显升高（３１８３６±２６．５４ｖｓ１７４９１±２１５８）ｎｇ／Ｌ，Ｐ＜００１；给予ｒｈＥＤＩＬ－８（２５０μｇ／ｋｇ）后，血浆６－ｋｅｔｏ－ＰＧＦ１α含量明显升高（３６８４７±１５６８ｖｓ１０３７６±１３１８）ｎｇ／Ｌ，Ｐ＜００１，其血浆水平与ＭＡＢＰ变化呈明显正相关（ｒ＝０．７４６，Ｐ＜００１）；ｒｈＥＤＩＬ－８对血浆ＴＸＢ２含量却无明显影响。结论：ｒｈＥＤＩＬ－８抗晚期失血性休克作用与其促进血管内皮细胞产生和释放ＰＧＩ２有关     

Development in in vitro toxicology

There are three principal pressures driving the development of in vitro toxicology: (1) the need for more efficient testing systems to cope with the large number of xenobiotics currently being developed; (2) public pressure to reduce animal experimentation; and (3) a need for a better understanding of the mechanisms of toxicity. Within this, in vitro toxicology is focused on local, systemic, and target-organ toxicity. It is becoming increasingly apparent that a step or decision-tree approach using input of a variety of experimental data (physicochemical properties, biokinetics, cytotoxicity) provides the most efficient system for predicting toxicity. Examples of the use of in vitro toxicity systems for prediction of systemic toxicity and target-organ (liver) toxicity are presented.Originally presented at ECCP 93.     

Age-related changes in polyamines in memory-associated brain structures in rats

Polyamines putrescine, spermidine and spermine are positively charged aliphatic amines and have important roles in maintaining normal cellular function, regulating neurotransmitter receptors and modulating learning and memory. Recent evidence suggests a role of putrescine in hippocampal neurogenesis, that is significantly impaired during aging. The present study measured the polyamine levels in memory-related brain structures in 24- (aged), 12- (middle-aged) and 4- (young) month-old rats using liquid chromatography/mass spectrometry and high performance liquid chromatography. In the hippocampus, the putrescine levels were significantly decreased in the CA1 and dentate gyrus, and increased in the CA2/3 with age. Significant age-related increases in the spermidine levels were found in the CA1 and CA2/3. There was no difference between groups in spermine in any sub-regions examined. In the parahippocampal region, increased putrescine level with age was observed in the entorhinal cortex, and age did not alter the spermidine levels. The spermine level was significantly decreased in the perirhinal cortex and increased in the postrhinal cortex with age. In the prefrontal cortex, there was age-related decrease in putrescine, and the spermidine and spermine levels were significantly increased with age. This study, for the first time, demonstrates age-related region-specific changes in polyamines in memory-associated structures, suggesting that polyamine system dysfunction may potentially contribute to aged-related impairments in hippocampal neurogenesis and learning and memory.     

Seasonal variations in acute toxoplasmosis in pregnant women in Slovenia

Between December 1999 and December 2004, 40 081 pregnant women were examined for toxoplasmosis with Toxo-IgG, Toxo-IgM enzyme immunoassay. Women with positive results were then retested with the Toxo-IgG avidity assay for recent toxoplasmosis. Recent acute toxoplasmosis in pregnant women was found to be significantly more frequent (p < 0.01) during winter than summer. The incidence of acute toxoplasmosis during winter-spring was also significantly more frequent (p < 0.025) than summer-autumn. This phenomenon should be taken into account when formulating preventive measures for toxoplasmosis, especially for pregnant women.     

休克过程中肾上腺髓质素变化的研究进展

Adrenomedullin (AM) is a new peptidergic regulator of vascular function. AM serves as a hormone, which has many biological properties, plays an important role in the many pathophysiological processes, especially shock. This review will highlight the structure, biological properties of AM and the relationship between AM and shock.     

Secular change in menarche in women in Madrid

The age at menarche was estimated by recollection in 1617 women between the ages of 18 and 60 in Madrid and a nearby suburb, Pinto. The population of Pinto is working-class and the Madrid group, taken from residential neighbourhoods , belongs to the upper middle class. In both groups we found a diminution in average age at menarche, from 14.04 to 13.02 years in Madrid and from 14.55 to 13.16 years from about 1935 to about 1965 in Pinto. These changes have been more intense in the group which is less well-off economically, where living conditions have varied much more drastically.     

Uteroglobin in the developing rabbit conceptus in vivo and in vitro

Summary Uteroglobin (UGL) was measured in day- 4 to day-10 rabbit conceptuses by a competitive ELISA. Levels in blastocyst fluid, tissues, coverings and in the early fetus were determined separately. The total amount of UGL increased from 18.4 ng to 6.8 g per conceptus. The UGL content of individual day-6 blastocysts was studied in vitro. Culturing was carried out up to 60 h in Ham's F10 medium with polyvinylpyrrolidone as macromolecular component, with and without progesterone, and with progesterone plus estradiol. UGL was determined in the blastocyst fluids, tissues with coverings and in the culture media. After labelling with [³⁵S]-methionine, protein patterns of total blastocysts and of culture media were analysed by two-dimensional gel electrophoresis and fluorography. The morphology of cultured blastocysts was examined by electron microscopy. During 60 h of culture, the blastocysts expanded in diameter by 84%, and released 19% of their initial UGL content into the medium, independent of the hormonal substitution. Neither de novo synthesis, nor degradation of UGL was found: the protein remained unlabelled in fluorography, and its total quantity was not significantly different from that of non-cultured controls. Trophoblast, endoderm and embryoblast cells showed well preserved cell organelles and intercellular junctions, while the morphological differentiation of the germ layer was inhibited.