再生肝胞液对肝损伤大鼠血清胰岛素及其与肝细胞结合的影响

研究了再生肝胞液(RLC)对实验性肝损伤大鼠血清胰岛素、C-肽水平及肝细胞结合A14[~(125)I]、胰岛素的影响;观察了RLC与胰岛素、高血糖合并应用对部分肝切除小鼠残余肝DNA合成的作用。结果表明:(1)氨基半乳糖(GaIN)中毒大鼠血清胰岛素水平降低与胰岛素分泌减少和肝细胞结合增加有关;RLC治疗后血清胰岛素的降低,仅与肝细胞结合增加有关。(2)胰岛素对肝再生的调控作用,在一定范围内,不仅仅取决于它在血液中的水平,而且取决于它与肝细胞结合的数量。     

蕨麻多糖保护D-氨基半乳糖急性肝损伤小鼠的作用机制

目的 考察蕨麻多糖(PAP)对D-氨基半乳糖(D-GlaN)诱导的急性肝损伤小鼠肝脏的保护作用机制.方法 60只昆明小鼠随机分为正常对照组、模型对照组、联苯双酯组(阳性对照)以及PAP 50、100、200mg/kg各剂量组,每组10只.先分别给予生理盐水、联苯双酯以及不同剂量受试药PAP,然后除正常对照组注射生理盐水外,其余5组均于给药7d后用8％ D-GlaN腹腔注射,建立D-GlaN急性肝损伤模型.24 h后处死,测定小鼠肝组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)、谷胱甘肽(GSH)等指标.结果 模型对照组小鼠肝组织中的MDA含量升高,SOD和GSH-Px活性降低,GSH含量降低,与正常对照组比较差异有统计学意义(P＜0.05,P＜0.01);联苯双酯以及50、100、200mg/kg各剂量PAP均可明显降低D-GlaN急性肝损伤小鼠肝组织中的MDA含量,提高SOD和GSH-Px的活性,增加GSH含量,与模型对照组相比差异有统计学意义(P＜0.05,P＜0.01).结论 PAP对D-GlaN急性肝损伤小鼠肝脏的保护作用可能与其清除自由基、保护细胞膜和抗脂质过氧化有关.     

D-氨基半乳糖盐酸盐溶液稳定性研究

目的 本文研究了Ｄ－氨基半乳糖盐酸盐溶液的化学稳定性,为该药物的制备、纯化以及实验动物肝细胞损伤模型用药提供必要的稳定性数据。方法 采用恒温加速实验,忱基半乳糖含量测定,研究不同ｐＨ条件下本品水溶液的稳定性,并与冰箱贮存样品比较。结果 实验表明,氨基半乳糖盐酸盐溶液ｐＨ值为３比较稳定,调ｐＨ值为７的本品水溶液不稳定,易分解,最多在５℃冰箱中保存５天,试样在加热情况下则迅速变色分解。结论 由于氨基己     

D-氨基半乳糖与脂多糖对小鼠肝脏损伤后再生修复的影响

目的观察部分肝切除联合D-氨基半乳糖(D-GaIN)、脂多糖对肝损伤后再生修复的影响。方法 40只BALB/c雄性小鼠随机均分为2组。D-GaIN/脂多糖/肝脏部分切除组:腹腔注射D-GaIN(500 mg/kg),1 h后注射脂多糖(50μg/kg);肝脏部分切除组:生理盐水代替D-GaIN和脂多糖,同样方法注射;两组小鼠在第2次腹腔注射24 h后行肝脏1/3切除。观察两组小鼠术后肝脏体质量比值、肝再生率、肝细胞损伤、增殖与肝卵圆干细胞增生。结果肝脏部分切除组术后第9天肝大体结构基本恢复正常,肝再生率为(22.26±105.93)%,而D-GaIN/脂多糖/肝脏部分切除组第14天肝质量较术前仍偏小,肝再生率为(9.49±32.55)%,P<0.001。D-GaIN/脂多糖/肝脏部分切除组术后肝窦和中央静脉充血,库普弗细胞增多;肝脏部分切除组术后第7天有明显肝细胞增殖,D-GaIN/脂多糖/肝脏部分切除组肝细胞增殖甚少。D-GaIN/脂多糖/肝脏部分切除组肝脏术后第3天开始出现肝卵圆干细胞增生,从汇管区开始向肝小叶内延伸以修复损伤。结论 D-GaIN联合脂多糖可部分抑制肝部分切除后小鼠成熟肝细胞增殖,D-GaIN/脂多糖/肝部分切除可诱导肝卵圆干细胞增生。     

Dual endothelin-converting enzyme/neutral endopeptidase blockade in rats with D-galactosamine-induced liver failure

Secondary activation of the endothelin system is thought to be involved in toxic liver injury. This study tested the hypothesis that dual endothelin-converting enzyme / neutral endopeptidase blockade might be able to attenuate acute toxic liver injury. - Male Sprague-Dawley rats were implanted with subcutaneous minipumps to deliver the novel compound SLV338 (10 mg/kg*d) or vehicle. Four days later they received two intraperitoneal injections of D-galactosamine (1.3 g/kg each) or vehicle at an interval of 12 hours. The animals were sacrificed 48 hours after the first injection. - Injection of D-galactosamine resulted in very severe liver injury, reflected by strongly elevated plasma liver enzymes, hepatic necrosis and inflammation, and a mortality rate of 42.9 %. SLV338 treatment did not show any significant effect on the extent of acute liver injury as judged from plasma parameters, hepatic histology and mortality. Plasma measurements of SLV338 confirmed adequate drug delivery. Plasma concentrations of big endothelin-1 and endothelin-1 were significantly elevated in animals with liver injury (5-fold and 62-fold, respectively). Plasma endothelin-1 was significantly correlated with several markers of liver injury. SLV338 completely prevented the rise of plasma big endothelin-1 (p<0.05) and markedly attenuated the rise of endothelin-1 (p = 0.055). - In conclusion, dual endothelin-converting enzyme / neutral endopeptidase blockade by SLV338 did not significantly attenuate D-galactosamine-induced acute liver injury, although it largely prevented the activation of the endothelin system. An evaluation of SLV338 in a less severe model of liver injury would be of interest, since very severe intoxication might not be relevantly amenable to pharmacological interventions.     

丹皮总甙防治大鼠急性肝损伤的实验研究

目的研究丹皮总甙对大鼠急性肝损伤的保护作用。方法分别采用四氯化碳（CCl4）和D-半乳糖胺（D—galactosamine,D—Gal）腹腔注射造成大鼠急性肝损伤,测定血清肝功能状态评价指标,并测体重、肝脏重、脾重、胸腺重,求脏器系数。同时切取肝脏检测肝糖原,并取肝组织作病理观察。结果丹皮总甙可显著降低CCl4和D—Gal诱导的急性化学性肝损伤大鼠血清ALT、AST、AIP水平及TBA利T—Bil含量。病理检查结果也显示有明显的保肝作用。结论丹皮总甙对CCl4利D—Gal所致大鼠急性肝损伤有保护作用。     

D-氨基半乳糖/脂多糖诱导急性肝衰竭大鼠肝细胞凋亡的电镜观察

目的通过透射电镜观察急性肝衰竭大鼠肝脏超微结构,以了解肝细胞凋亡的形态学变化。方法给予雌性Wistar大鼠D-氨基半乳糖/脂多糖联合腹腔注射,计算其死亡率及生存时间,动态观察给药后4、8、12小时肝功能和组织病理学变化,并以TUNEL法检测和电镜观察原位细胞凋亡。结果实验组80%大鼠死于急性肝衰竭,平均生存时间为15.6±1.8小时。给药后4小时电镜观察,发现肝细胞线粒体肿胀、内质网扩张,胞浆包含体形成,部分细胞核呈早期凋亡表现,细胞内凋亡小体形成;8小时时,肝细胞凋亡明显增多并呈不同阶段表现,凋亡肝细胞内线粒体病变程度不一;TUNEL检测给药后8小时肝细胞,凋亡指数达高峰,与电镜观察结果一致。结论肝细胞凋亡为D-氨基半乳糖/脂多糖致急性肝衰竭大鼠肝细胞的主要病理形态学表现,这可能为该类型肝衰竭的主要病理学变化基础。     

人肝刺激因子的提取及其保肝作用的初步观察

采用水囊引产眙儿(胎龄4～6个月),提取肝刺激因子(hHSS),用~3H—胸腺嘧啶核苷测其活性,观察到 hHSS 可使34%肝切除的大鼠对~3H—胸腺嘧啶核苷掺入再生肝 DNA 率明显增加。将 hHSS 预先注入半乳糖胺损伤的小鼠体内,结果观察到:hHSS 极明显地降低半乳糖胺中毒的死亡率(P<0.01),明显地抑制半乳糖胺所致的血清 GPT 和 GOT 的高水平。电镜检查表明,hHSS 可保护肝细胞的超微结构(线拉体、内质网等)免受半乳糖胺的损伤。这些结果证明,从人胎肝中可提取 hHSS,而 hHSS 具有保护肝脏免受肝毒剂—半乳糖胺的毒害作用。     

Inhibition of Nitric Oxide Modulates the Effect of Oral Arginine Supplementation in Acute Liver Injury

Background: Arginine possesses numerous unique and advantageous biochemical and pharmacologic properties. We have previously shown that arginine supplementation in an acute liver injury model reduces both the extent of the liver injury and bacterial translocation. We therefore studied the role of nitric oxide on the effects of oral arginine supplementation in acute liver injury, bacterial translocation, ileal and cecal mucosal nucleotides, and RNA and DNA, to investigate pathogenetic mechanisms. Methods: Sprague-Dawley rats were divided into normal, liver injury control, N-nitro-L-arginine methyl ester (L-NAME), arginine, and L-NAME + arginine supplementation groups. Oral supplementation was performed daily through a nasogastric tube for 8 days. Acute liver injury was induced on the 8th day by intraperitoneal injection of D-galactosamine (1.1 g/kg body weight). Twenty-four hours after the liver injury, liver function tests, bacterial translocation, and ileal and cecal mucosal nucleotides, RNA, and DNA were evaluated. Results: Bilirubin and liver enzymes increased significantly in the L-NAME group compared with the arginine group, whereas the liver enzymes increased significantly compared wim the liver injury control group. In the L-NAME group the number of bacteria translocated to the portal and arterial blood increased significantly compared with all groups. In the arginine group the bacteria translocated to the liver and mesenteric lymph nodes decreased significantly compared with the liver injury control and L-NAME groups. The ileal and cecal mucosal nucleotides, RNA, and DNA in the arginine group increased significantly compared with the normal, liver injury, and L-NAME groups. Conclusions: Nitric oxide plays a role in the beneficial effect of the arginine supplementation in acute liver injury. It significantly improves the liver damage indicated by the increase of liver enzymes when its production was inhibited by L-NAME. Nitric oxide has a role in bacterial translocation since the number of bacteria significantly increased in arterial and portal blood when L-NAME was used to inhibit its production. Furthermore, arginine supplementation improved mucosal nucleotides, RNA, and DNA in ileum and colon.     

Development of a rat model of D-galactosamine/lipopolysaccharide induced hepatorenal syndrome

AIM:To develop a practical and reproducible rat model of hepatorenal syndrome for further study of the pathophysiology of human hepatorenal syndrome. METHODS:Sprague-Dawley rats were intravenously injected with D-galactosamine and lipopolysaccharide(LPS) via the tail vein to induce fulminant hepatic failure to develop a model of hepatorenal syndrome. Liver and kidney function tests and plasma cytokine levels were measured after D-galactosamine/LPS administration,and hepatic and renal pathology was studied. Glomerular filtration rate was detected in conscious rats using micro-osmotic pump technology with fluorescein isothiocyanate-labelled inulin as a surrogate marker.RESULTS:Serum levels of biochemical indicators including liver and kidney function indexes and cytokines all significantly changed,especially at 12 h after D-galactosamine/LPS administration [alanine aminotransferase,3389.5 ± 499.5 IU/L; blood urea nitrogen,13.9 ± 1.3 mmol/L; Cr,78.1 ± 2.9 μmol/L; K+,6.1 ± 0.5 mmol/L; Na+,130.9 ± 1.9 mmol/L; Cl-,90.2 ± 1.9 mmol/L; tumor necrosis factor-α,1699.6 ± 599.1 pg/m L; endothelin-1,95.9 ± 25.9 pg/m L; P 0.05 compared with normal saline control group]. Hepatocyte necrosis was aggravated gradually,which was most significant at 12 h after treatment with D-galactosamine/LPS,and was characterized by massive hepatocyte necrosis,while the structures of glomeruli,proximal and distal tubules were normal. Glomerular filtration rate was significantly decreased to 30%-35% of the control group at 12 h after D-galactosamine/LPS administration [Glomerular filtration rate(GFR)1,0.79 ± 0.11 m L/min; GFR2,3.58 ± 0.49 m L/min·kg BW-1; GFR3,0.39 ± 0.99 m L/min·g KW-1]. The decreasing timing of GFR was consistent with that of the presence of hepatocyte necrosis and liver and kidney dysfunction.CONCLUSION:The joint use of D-galactosamine and LPS can induce liver and kidney dysfunction and decline of glomerular filtration rate in rats which is a successful rat model of hepatorenal syndrome.