不同原因诱导大鼠腹主动脉移植硬化的组织病理比较

目的：研究不同原因诱导的大鼠腹主动脉移植硬化的组织病理学改变。方法：140只大鼠随机分组：A组为非移植组,B组为同品系移植缺血小于30min组;C组为同品系移植缺血4h组;D组为异品系移植缺血小于30min组,术后7,15,30,60天切取植入的腹主动脉进行光镜,电镜检查。结果：移植7－15天时C组动脉内膜有多量多形粒细胞和单个核细胞粘附,浸润,电镜检查多形核粒细胞为中性粒细胞,而D组移植动脉各层均有大量的淋巴细胞浸润,移植30－60天时C组,D组移植动脉内膜均有显著增厚,增生的内膜均由单核／巨噬细胞和平滑肌细胞构成,但前者无中膜层平滑肌坏死及弹力膜断裂现象。结论：中性粒细胞在缺血／再灌注损伤诱导的同品系大鼠腹主动脉移植硬化发挥了重要作用,其机制值得进一步研究。     

移植动脉新生内膜平滑肌细胞来源于受体骨髓细胞的实验依据

目的： 研究大鼠移植动脉新生内膜平滑肌细胞Sry基因表达，探讨移植物动脉硬化新生内膜平滑肌细胞的来源。方法: 将雄性Wistar大鼠骨髓细胞移植到雌性大鼠体内，制备嵌合体大鼠；4周后建立大鼠腹主动脉移植慢性排斥反应模型，分为4组：雌性同系移植组、雌性异系移植组、雄性异系移植组、嵌合体异系移植组。移植术后8周，取移植动脉组织标本，进行病理组织学观察与免疫组化染色，分析移植动脉新生内膜增生及新生内膜细胞α-SMA的表达；采用显微切割技术收集新生内膜平滑肌细胞，用PCR扩增方法检测细胞Sry基因表达，分析新生内膜平滑肌细胞与受体骨髓细胞的关系。结果: 异系移植组移植动脉新生内膜中α-SMA表达阳性平滑肌细胞大量增生，致动脉内膜显著增厚，动脉壁新生内膜面积及新生内膜/中膜面积比均显著高于同系移植组(P<0.01)。PCR分析显示，嵌合体异系移植组和雄性异系移植组一致，在约225 bp处均有1条特异性扩增条带，而雌性异系移植组则无相应的核酸扩增条带。结论: 受体骨髓细胞作为移植物血管新生内膜平滑肌细胞的来源，参与移植物动脉硬化发生和发展。     

阿托伐他汀对大鼠自体移植静脉内膜增生的影响

目的： 探讨新型降脂药阿托伐他汀对自体移植静脉内膜增生的影响。 方法： 将Wistar大鼠颈外静脉移植于腹主动脉,建立大鼠自体静脉移植模型,实验分为3组：假手术组、移植对照组和移植实验组。自术后第1 d起,对移植实验组大鼠经胃管灌注给予阿托伐他汀(5 mg·kg-1·d-1)处理。干预4周后取移植静脉组织标本,制备4 μm厚组织切片,行病理组织学观察分析移植静脉内膜增生情况,行免疫组化染色分析新生内膜细胞SMα-actin和PCNA的表达情况。 结果： 移植对照组和实验组移植静脉内皮下层SMα-actin染色阳性平滑肌细胞大量增生,导致静脉内膜显著增厚,血管管腔明显狭窄。新生内膜定量分析显示移植实验组移植静脉内膜增生受到明显抑制,其新生内膜面积及新生内膜/中膜面积比均显著低于对照组(P<0.01);并且实验组移植静脉新生内膜细胞PCNA标记指数显著低于对照组(P<0.01)。 结论： 阿托伐他汀通过抑制新生内膜平滑肌细胞的增殖能有效抑制自体移植静脉内膜增生的发生发展,在防治血管重建术后再狭窄方面显示出良好的应用前景。     

镁合金支架在兔腹主动脉中的降解北大核心

背景:国外研究发现镁合金支架是安全有效的,国内对于镁合金支架降解性能的研究不多。目的:探讨可降解AZ31镁合金支架在兔腹主动脉中的降解情况及降解过程对血管的影响。方法:在28只新西兰大白兔腹主动脉植入可降解AZ31镁合金支架,在植入的30,60,90,120 d进行X射线检查及支架植入段血管组织学观察。结果与结论:(1)X射线检查:植入后30 d,支架完全扩张,结构完整;植入后60 d,支架变形,部分支架断裂,失去支撑作用;植入后90 d,只有少量支架支杆残留,大部分支架已降解;植入后120 d,血管中无支架支杆残留,支架已完全降解;(2)组织学观察结果:植入后60 d的剩余支架支杆数小于植入后30 d(P<0.05),植入后90 d的剩余支架支杆数小于植入后30,60 d(P<0.05),植入后120 d的剩余支架支杆数小于植入后30,60,90 d(P<0.05);剩余支杆数和天数呈负相关,支架完全降解天数为植入后124.8 d。植入90 d的血管内膜面积大于植入后30,60,120 d(P<0.05),血管管腔面积小于小于植入后30,60,120 d(P<0.05);后3个时间点的血管内膜面积与血管管腔面积比较差异无显著性意义;(3)结果表明,可降解AZ31镁合金支架在大白兔腹主动脉内完全降解时间为124.8 d,在支架植入90 d时血管内膜增生和管腔狭窄最明显,90 d后血管内膜增生和管腔狭窄逐渐减轻。     

异种移植建立的大鼠腹主动脉瘤形态学特征

目的: 建立和鉴定一种新型腹主动脉瘤动物模型, 为腹主动脉瘤的进一步研究提供基础。方法: 选取豚鼠肾下腹主动脉组织1 cm, 正位替换SD大鼠同长度腹主动脉; SD大鼠腹主动脉原位离断后吻合分别作为对照。分别于术后4周动态观测和比较移植腹主动脉直径、腔面积等形态学变化; 计算机图像技术半定量分析弹力纤维、胶原纤维及平滑肌变化。结果: 存活受体中88%移植腹部主动脉血流通畅, 无移植物或吻合口狭窄, 无腔内血栓形成。4周内, 异种移植组腹主动脉直径随时间延长逐渐扩张, 与对照组有显著差异; 腹主动脉扩张率与弹力蛋白、中膜平滑肌变化呈现显著负相关。结论: 免疫炎症损伤介导的豚鼠-SD大鼠异种移植腹主动脉瘤是一稳定可靠的动物模型。     

动脉粥样硬化大鼠血管损伤后局部组织学结构的变化

目的建立大鼠颈总动脉球囊损伤模型，了解血管成形术后再狭窄的发生规律及病理机制。方法在大鼠动脉粥样硬化病变的基础上，使用2F球囊导管损伤大鼠左侧颈总动脉，观察术后不同时期内膜、中膜增生的动态改变；对血管壁增殖的细胞进行鉴定；观察血管壁平滑肌细胞表型标志物SMα—actin表达的变化。结果损伤后7天薪生内膜开始形成，至3月时内膜增厚达最大，管腔明显狭窄，损伤动脉壁可见细胞大量增殖，大部分为平滑肌细胞。损伤早期血管壁表达SMα—actin减少，至损伤后期逐渐恢复至原有水平。结论应用球囊导管可以成功建立大鼠血管损伤动物模型，损伤后新生内膜增生导致管腔狭窄，平滑肌细胞的表型改变、迁移及增殖是内膜过度增生的病理基础。     

强力霉素影响基质金属蛋白酶活性和血管重构的实验研究

目的：观察强力霉素对损伤动脉组织中基质金属蛋白酶（MMP）活性的抑制作用，并探讨强力霉素对血管平滑肌细胞增殖、动脉内膜增生、管腔重构的影响。方法:球囊导管扩张动脉的方法建立大鼠颈总动脉损伤模型。治疗组用强力霉素30 mg·kg^-1·d^-1干预。明胶酶谱法测定损伤动脉组织中MMPs的活性。用HE染色、VVG染色、免疫组化标记α-actin和增殖细胞核抗原的方法观察损伤动脉内膜厚度、管腔重构及平滑肌细胞增殖的情况。结果:①强力霉素治疗组MMP-9活性在术后24 h、3 d分别比对照组低26.3％、34.5％（P<0.01）；MMP-2活性在术后7 d比对照组低40.0％（P<0.01）。②强力霉素治疗使术后7 d内膜平滑肌细胞增殖率（43.23％±1.06％）显著低于对照组（62.76％±1.02％）（P<0.01）；使术后14 d、28 d新生内膜厚度比对照组分别少32.0％、38.8％（P<0.01），而管腔面积比对照组多58.0％、90.4％（P<0.01） 。结论：强力霉素可以显著降低血管损伤后MMPs活性，抑制内膜平滑肌细胞的增殖、新生内膜增生以及管腔重构，提示它可能具有防治PTCA术后再狭窄的作用。     

瑞舒伐他汀对Medtronic球囊导管损伤大鼠颈动脉平滑肌细胞增殖及凋亡的影响

背景:球囊扩张及支架置入后再狭窄、管腔丢失等问题制约了支架置入治疗的进一步发展,血管内膜增殖和凋亡在再狭窄中的作用及干预方法尚在积极探索中。目的:采用Medtronic球囊建立大鼠颈动脉球囊损伤模型,观察瑞舒伐他汀对球囊损伤大鼠颈动脉平滑肌细胞增殖及凋亡的影响。方法:将雄性SD大鼠随机数字表法分为球囊损伤组和治疗组。均采用Medtronic球囊建立大鼠颈动脉球囊损伤模型,并取球囊损伤组大鼠的右侧颈总动脉(未行球囊损伤)作为正常对照。治疗组于球囊损伤前3d始连续给予瑞舒伐他汀5mg/(kg·d)灌胃,球囊损伤组给予9g/L氯化钠溶液灌胃。术后7,14d取颈总动脉进行苏木精-伊红染色,免疫组织化学检测SMα-actin、增殖细胞核抗原,采用TUNEL法检测平滑肌细胞凋亡情况。结果与结论:与球囊损伤组比较,治疗组造模后14d,损伤血管新生内膜面积、新生内膜/中膜面积比值明显减少(P0.05),管腔面积增加26%;增殖细胞核抗原阳性细胞率降低,凋亡阳性细胞率增高(P0.05)。提示支架置入球囊损伤前给予瑞舒伐他汀可抑制大鼠颈动脉球囊损伤后新生内膜增生及新生内膜细胞的增殖,促进平滑肌细胞的凋亡,从而减少动脉新生内膜形成,抑制再狭窄。     

纤维蛋白沉积与大鼠主动脉球囊损伤后肌内膜增殖的关系

目的：利用大鼠胸主动脉球囊内皮剥脱术模型，探讨纤维蛋白（原）与肌内膜增殖的关系。方法：将６４只Ｗｉｓｔａｒ大鼠随机分为正常组、假手术组和剥脱组。剥脱组大鼠又分别在术后１０ｍｉｎ、１、３、７、１４、２１天处死取材。结果：大鼠胸主动脉免疫组织化学研究发现，正常组和假手术组大鼠血管壁无纤维蛋白（原）沉积，术后１０ｍｉｎ在血管腔表面即有一层致密的纤维蛋白（原）沉积，然后随着术后时间的延长，纤维蛋白（原）逐渐渗入到增殖的新生内膜中，中膜中未见有纤维蛋白（原）的沉积。结论：纤维蛋白（原）可能在内皮剥脱后的血管平滑肌细胞增殖中起一定作用。     

大鼠主动脉支架术模型的建立及光学相干断层扫描评估

目的 建立大鼠主动脉支架术动物模型,为冠状动脉支架再狭窄等研究提供实用的小动物平台。方法 SD雄性大鼠18只(500～700 g),麻醉消毒后,经左髂动脉切口于肾动脉分叉处上方10 mm的腹主动脉处行2.5 mm×16.0 mm支架植入,缝合左髂动脉切口。术前及术后即刻、1个月、2个月、6个月对支架段血管进行光学相干断层扫描(OCT)检测分析。结果 通过切开髂动脉于大鼠腹主动脉行支架植入术均获成功,无大鼠死亡及跛行。OCT检查结果显示：术前大鼠主动脉内膜显示清晰,直径约2 mm;术后即刻支架钢梁突出内膜、贴壁良好;术后1个月可见内皮细胞覆盖;术后2个月见少量内膜增生;术后6个月可见较明显的内膜增生,未见血栓形成。结论 大鼠经髂动脉切开主动脉支架植入可行性强,可通过OCT进行精准评估。     

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.     

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.     

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.     

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.