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61.
Ethanol is known as a potent teratogen responsible for the fetal alcohol syndrome characterized by cognitive deficits especially pronounced in juveniles but ameliorating in adults. Since the mechanisms of these deficits and following partial recovery are not fully elucidated, the aim of the present study was to investigate the process of synaptogenesis in the hippocampus over the first two months of life in control and fetal-alcohol rats. Ethanol was delivered to the pregnant dams by intragastric intubation throughout 7–21 gestation days at the daily dose of 6 g/kg generating a mean blood alcohol level of 246.6 ± 40.9 mg/dl on gestation day 20. The spine densities as well as the expression of pre- and postsynaptic proteins, synaptophysin (SYP) and PSD-95 protein, were evaluated for three distinct hippocampal regions: CA1, CA2+3, and DG and four postnatal days: PD1, PD10, PD30 and PD60, independently. Our results confirmed an intensive synaptogenesis within the brain spurt period (first 10 postnatal days), however, the temporal pattern of changes in the SYP and PSD-95 expression was different. The ethanol exposure during half of the 1st and the whole 2nd human trimester equivalent resulted in an overall trend toward lower values of synaptic indices at PD1 with a fast recovery from these deficits observed already at PD10. At PD30, around the age when the most pronounced behavioral deficits have been previously reported in juvenile fetal-alcohol subjects, no significant changes were found in either the hippocampal levels of synaptic proteins or in the spine density in principal hippocampal neurons.  相似文献   
62.
The aim of the study was to investigate the presence and distribution of the chromogranin A-derived peptide catestatin in the rat eye and trigeminal ganglion by immunofluorescence using an antibody which recognizes not only free catestatin but also larger fragments containing the sequence of catestatin. Western blots were performed in an attempt to characterize the immunoreactivities detected by the catestatin antiserum. Sparse immunoreactive nerve fibers were visualized in the corneal stroma, in the chamber angle, in the sphincter muscle but also in association with the dilator muscle, in the stroma of the ciliary body and processes, but dense in the irideal stroma, around blood vessels at the limbus and in the choroid and in cells of the innermost retina representing amacrine cells as identified by colocalization with substance P. Furthermore, catestatin-immunoreactivity was detected in the trigeminal ganglion in small to medium-sized cells and there were abundant catestatin-positive nerve fibers stained throughout the stroma of the ganglion. Double immunofluorescence of catestatin with substance P revealed colocalization both in cells of the trigeminal ganglion as well as in nerve fibers in the choroid. The immunoreactivities are present obviously as free catestatin and/or small-sized catestatin-containing fragments in the retina and ocular nerves but as large processed fragments as well, weak in the retina and more prominent in remaining ocular tissues, possibly in endothelial cells. This indicates that this peptide is a constituent of sensory neurons innervating the rat eye and the presence in amacrine cells in the retina is typical for neuropeptides. Catestatin is biologically highly active and might be of significance in the pathophysiology of the eye.  相似文献   
63.
目的:观察电针足三里穴对失血性休克大鼠肠胶质细胞形态的影响,探讨电针足三里穴治疗胃肠疾病的机制。方法:将18只SD雄性大鼠随机分为假手术组、模型组和电针组,每组6只。按总血容量的45%放血制备失血性休克模型。电针组于制模完成后10 min电针足三里穴(持续刺激1.5 h,2-100 Hz,2 mA);模型组同样方法电针非经非穴;假手术组只分离股动、静脉不放血。失血后6 h后处死大鼠,取肠道组织制作肠肌间神经丛全层铺片,采用免疫荧光法进行肠胶质纤维酸性蛋白(GFAP)染色,荧光显微镜下观察肠胶质细胞形态,同时对肠道GFAP蛋白含量进行WesternBlot测定。结果:失血后6 h,肠胶质细胞出现形态学异常,细胞变形并且荧光增强,突触模糊、中断;电针足三里穴能减轻肠胶质细胞形态学异常,增加荧光强度。与假手术组相比,模型组GFAP表达量增加,但电针足三里穴后GFAP的表达量增加更为显著(P〈0.05)。结论:大鼠失血性休克后电针足三里穴能激活并保护肠胶质细胞。  相似文献   
64.

Purpose

The aim of this study was to investigate the effects of iloprost (IL) on ischemia-reperfusion injury in a rodent model.

Materials and methods

Twenty-four Wistar Albino rats were randomized into four groups (n = 6). Laparotomy was performed in all groups under general anesthesia. Only laparotomy was applied in group S (Sham). Ischemia-reperfusion group (group I/R) underwent ischemia and reperfusion performed by clamping and declamping of the infrarenal abdominal aorta for 120 min. The iloprost group (group IL) received intravenous infusion of IL 0.5 ng/kg/min, without I/R. Group I/R + IL received intravenous infusion of IL 0.5 ng/kg/min immediately after 2 h period of ischemia. At the end of the reperfusion period, all rats were killed under anesthesia and skeletal muscle samples of lower extremity were harvested for biochemical and histopathologic analyses.

Results

Tissue levels of endothelial nitric oxide were significantly higher in I/R groups than those in groups S and IL. The heat shock protein 60 levels were higher in group I/R than the other groups. But the heat shock protein 60 levels in group I/R + IL were found to be similar with the groups S and IL. Malondialdehyde levels were significantly higher in group I/R. On the other hand, in group I/R + IL, malondialdehyde levels were higher than those in groups S and IL but lower than those in group I/R. Superoxide dismutase (SOD) enzyme activities were found to be significantly lower in group I/R than the other groups. Also in group I/R/I, the SOD enzyme activities were higher than those in group I/R. But, in group I/R + IL, SOD levels were found to be higher than those in group I/R but lower than those in groups S and IL.

Conclusions

These results indicate that IL has protective effects on I/R injury in skeletal muscle in a rodent model.  相似文献   
65.

Background

Crush syndrome (CS) has been reported in disasters, terrorist incidents, and accidents, and the clinical and pathologic picture has gradually been clarified. Few lethal and reproducible animal models of CS with use of a quantitative load are available. A new model is needed to investigate pathologic and therapeutic aspects of this injury.

Materials and methods

Using a device built from commercially available components, both hindlimbs of anesthetized rats were respectively compressed for 6 h using 3.6-kg blocks. The effects of trunk warming alone without compressed hindlimbs (Group A), non-warming at room temperature (Group B), whole-body warming including compressed hindlimbs (Group C), or warming of compressed hindlimbs alone (Group D) during compression were examined. Survival rates were compared and hematological and histologic analyses were performed at specific time points after compression release.

Results

Limb or whole-body warming significantly worsened the survival of rats. We found a much lower survival rate of 0%–10% in animals, in which the hindlimbs were warmed during compression (Groups C and D) at 12 h after compression release, compared with 90%–100% in animals without warming of the hindlimbs (Groups A and B). Groups C and D showed significantly enhanced hyperkalemia at ≥4 h after compression release and all blood samples from dead cases showed hyperkalemia (>10 mEq/L).

Conclusions

We developed a new lethal and reproducible rat CS model with a quantitative load. This study found that warming of compressed limbs worsened the survival rate and significantly enhanced hyperkalemia, apparently leading to cardiac arrest.  相似文献   
66.

Background

The aim of the present study was to develop a rat model of colonic microperforation secondary to thermal injury for future studies to assess new treatments.

Methods

Twenty-four male Sprague–Dawley rats were used in this study. Hot biopsy forceps were used for all treatments. All lesions were created in proximal left colon using the soft coagulation setting. The power setting tested was 40 W, and the durations of monopolar soft coagulation application evaluated were 2, 3, and 4 s.

Results

In the acute phase, 48 h after thermal injury, durations of cautery of 2 and 3 s resulted in transmural necrosis, whereas with 4 s microperforation was obtained. In the late phase, 7 d after the damage, only duration of cautery of 4 s showed deep cautery effects, with signs of peritonitis.

Conclusions

We determined optimal power settings and duration of therapy in a rat model for producing electrocautery that involves transmural necrosis with microperforation.  相似文献   
67.
目的:通过观察实验大鼠口腔溃疡愈合情况及检测血清中EGF、及口腔黏膜EGFR水平,来评价口疮1号方对实验性大鼠口腔溃疡的治疗效果,并探讨其作用机制,从而为临床应用提供理论依据。方法:利用化学药物灼烧法复制口腔溃疡模型。利用酶联免疫吸附法(ELISA)检测正常大鼠及模型大鼠血清中EGF水平。并取正常及有损伤的口腔黏膜组织,做病理检查。及利用免疫组化方法检测EGFR水平。再将剩余模型大鼠随机分为口疮1号方实验组和生理盐水对照组,5d后,观察每组大鼠一般症状体征及口腔溃疡变化情况,检测血清中EGF水平、及口腔黏膜组织EGFR水平。结果:模型组大鼠血清中EGF、及大鼠黏膜EGFR含量水平较正常大鼠显著降低(P〈0.01)。口疮1号方实验组与生理盐水对照组相比,体重增加,口腔溃疡面积缩小。两组大鼠血清中EGF及口腔黏膜中EGFR水平均有所升高,实验组EGF,EGFR水平较对照组升高快,两组之间有显著差异(P〈0.01)。结论:口疮1号方可以显著改善口腔溃疡症状,促进溃疡愈合。口疮1号方可以调节口腔溃疡时EGF、EGFR水平,增强口腔黏膜修复能力。  相似文献   
68.
目的:探讨组蛋白去乙酰化酶8(histone deacetylase 8,HDAC8)对大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)成骨分化的影响。方法:通过全骨髓贴壁法体外分离培养大鼠 BMSCs,转染 HDAC8过表达慢病毒载体,并于矿化诱导液中培养7 d后,实时荧光定量PCR、Western blot检测BMSCs成骨分化能力的变化;矿化诱导14 d后,茜素红钙结节染色检测BMSCs矿化能力的变化。组蛋白去乙酰化酶抑制剂---曲古抑菌素A(trichostatin A,TSA)刺激转染HDAC8过表达慢病毒载体的 BMSCs,于矿化诱导液中培养7 d后,实时荧光定量 PCR及 Western blot检测 TSA刺激前后过表达 HDAC8的BMSCs成骨分化能力的变化。结果:HDAC8过表达组经矿化诱导7 d 后,成骨分化相关基因 mRNA、蛋白表达水平均低于空白对照组;经14 d矿化诱导后,HDAC8过表达组茜素红钙结节的着色程度及范围低于空白对照组。TSA 刺激的 HDAC8过表达组矿化诱导7 d后,成骨分化相关基因 mRNA及蛋白的表达均高于未加刺激组(P<0.05)。结论:HDAC8对大鼠 BMSCs成骨分化具有抑制作用。  相似文献   
69.
目的探讨肾缺血-再灌注损伤(IRI)大鼠基质细胞衍生因子(SDF)-1、细胞间黏附分子-1(ICAM-1)与肾小管坏死评分的相关性。方法将60只SD大鼠随机分成手术组、假手术组两组,每组各30只。根据手术后检测时间不同,每组再分为6个不同时段的亚组(1、6、12、24、48、72 h组),每个亚组有5只大鼠。手术组建立大鼠肾IRI模型,假手术组大鼠仅予游离双侧肾动脉后缝合切口。检测各个时间点肾功能、肾小管坏死评分及肾脏组织SDF-1、ICAM-1表达变化。对手术组大鼠肾组织SDF-1、ICAM-1表达与肾功能和肾小管坏死评分进行Pearson直线相关分析。结果手术组术后血尿素氮(BUN)、血清肌酐(Scr)较术前及相应时间段假手术亚组明显升高(均为P0.05),且于术后12 h显著升高,高峰期在术后48 h。手术组肾小管坏死评分随时间的延长逐渐增高(均为P0.05);肾小管坏死评分最高在手术48 h组(P0.05)。与手术1 h组比较,手术6 h组大鼠肾组织SDF-1、ICAM-1表达开始明显增多(均为P0.05);手术后48 h达高峰,于手术后72 h开始下降。手术组的肾组织SDF-1、ICAM-1表达与术后各时间段BUN、Scr、肾小管坏死评分呈正相关(r=0.614、0.662、0.751;0.640、0.703、0.785;均为P0.05)。结论当大鼠肾组织发生IRI时,SDF-1、ICAM-1表达上调,BUN、Scr升高,肾小管坏死评分升高,而且SDF-1、ICAM-1的表达与BUN、Scr、肾小管坏死评分呈正相关,提示SDF-1、ICAM-1表达增高程度可以作为反映肾IRI后严重程度的指标。  相似文献   
70.
目的探讨大鼠肾移植模型手术的改良方法。方法供体Sprague-Dawley(SD)大鼠21只,受体Wistar大鼠42只。采用双侧供肾。受体左肾切除后借助自制导管,行受体肾动脉与供体肾动脉、受体肾静脉与供体下腔静脉端端吻合,供体输尿管带膀胱瓣与受体膀胱吻合,最后切除右肾,腹腔内注入头孢米诺10 mg,关腹。记录手术时间,动、静脉吻合时间,冷、热缺血时间等手术数据;术后大鼠存活3 d认为模型建立成功,计算建模成功率,分析死亡原因。结果供体手术时间为(32.7±5.6)min,供肾修整时间为(4.2±1.1)min。受体手术时间为(42.3±4.9)min,其中动脉吻合时间为(10.1±3.2)min,静脉吻合时间为(13.9±2.5)min,尿路重建时间为(6.3±1.4)min。热缺血时间为(5.4±1.8)s,冷缺血时间为(56.2±7.3)min。42只受体大鼠中,建模成功40只,成功率为95%。另2只受体大鼠死亡,其中1只死于血管吻合口出血,1只死于尿瘘引致的腹膜炎。结论采用改良的血管端端吻合法建立大鼠肾移植模型具有操作简单、手术时间短、成功率高的特点。  相似文献   
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