氯化镉对大鼠原代星形胶质细胞凋亡的影响

目的研究氯化镉对星形胶质细胞凋亡的影响。方法取处于对数生长期的细胞,以终浓度为0(对照)、2.5、5、10、20、40μmol/L氯化镉溶液染毒12、24 h,采用MTT实验测定细胞的存活率;以终浓度为0(对照)、2.5、5、10、20μmol/L氯化镉溶液染毒12 h,采用Annexin V-FITC/PI双染流式细胞术测定细胞的凋亡率。结果与对照组相比,5~40μmol/L氯化镉染毒12、24 h时大鼠星形胶质细胞的存活率均较低,5~20μmol/L氯化镉染毒12 h时大鼠星形胶质细胞的凋亡率均较高,差异均有统计学意义(P0.05);且随着氯化镉染毒浓度的升高,大鼠星形胶质细胞的存活率呈下降趋势,而凋亡率呈上升趋势。结论氯化镉对星形胶质细胞具有明显的毒性作用,可诱导星形胶质细胞凋亡。     

同型半胱氨酸对大鼠主动脉内皮细胞生长和功能的影响

Objective To study the possible mechanism of the effects ofhomocysteine on the formation of atherosclerosis (AS). Methods Aortic endothelial cells of SD rat were cultured and treated with a concentrated homocysteine for 24h,the cultured cells and the contents in the medium were studied by MTT colorimetric assay,flow cytometric method (FCM),PGI２,thromboxane A2,(TXA２),nitric oxide (NO),endothelin(ET) in the contents were examined. Results (1)homocysteine had an inhibitory effect on the proliferation of rat aortic endothelial cells;(2)homocysteine prevented rat aortic endothelial cell form G1-phase into S-phase in DNA synthesis;(3)vascular relaxing factor NO,PGI2 content in culture media in homocysteine group was significantly lower than that of control group;(4)vasoconstrictors-TXA2,ET were markedly higher than that of control group;(5)ox-LDL which had a bad effect on endothelial was higher than that of control group. Conclusions In the experimental model study,homocysteine was proved having a definite harmful effect on the aortic endothelial cells and this initial damage might play a very important role in the process of AS formation.     

镉对肾上腺皮质细胞线粒体功能的影响

目的 研究镉对肾上腺皮质细胞线粒体功能的影响,为探讨其内分泌毒作用机制提供依据。方法 原代分离培养豚鼠肾上腺皮质细胞,用氯化镉（ＣｄＣｌ２）０、６．２５、１２．５０、２５．００、５０．００、１００．００、２００．００ｕｍｏｌ／ｌ处理细胞１ｈ,以５０ｕｍｏｌ／Ｌ ＣｄＣｌ２处理细胞０、１５、３０、６０、１２０、２４０ｍｉｎ,观察ＣｄＣｌ２对肾上腺皮质细胞线粒体功能毒作用的剂量－效应及时间－效应关系。应用四甲基偶氮唑蓝（ＭＴＴ）试验检测线粒体酶活力,用流式细胞仪结合罗丹明１２３（Ｒｈ１２３）和碘化丙啶（ＰＩ）双标记法检测线粒体膜电位（ＭＭＰ）和细胞存活状态。结果 ＣｄＣｌ２引起细胞线粒体酶活力及ＭＭＰ降低：以６．２５～２００．００ｕｍｏｌ／Ｌ ＣｄＣｌ２染毒细胞１ｈ,对照组ＭＴＴ的平均吸光度（Ａ５７０ｎｍ）值为０．     

氯化镧对原代培养的星形胶质细胞的氧化损伤作用

目的研究氯化镧(lanthanum chloride,LaCl3)对原代培养的星形胶质细胞的氧化损伤作用。方法原代培养的星形胶质细胞经0、0.25、0.5、1.0 mmol/L LaCl3处理24 h后,采用MTT法和Alamar Blue还原法检测星形胶质细胞的存活率,并测定星形胶质细胞中谷胱甘肽(glutathione,GSH)、丙二醛(malondialdehyde,MDA)含量和谷胱甘肽过氧化物酶(glutathione peroxydase,GSH-Px)活性。结果各LaCl3处理组星形胶质细胞的存活率均显著低于对照组,且具有一定的剂量-反应关系。0.25 mmol/L LaCl3组星形胶质细胞的GSH含量和GSH-Px活性显著低于对照组;0.5 mmol/L LaCl3组星形胶质细胞的GSH含量和GSH-Px活性显著低于对照组和0.25 mmol/L LaCl3组;1.0mmol/LLaCl3组星形胶质细胞的GSH含量和GSH-Px活性分别降低至对照组的66%和43%,均显著低于对照组、0.25和0.5 mmol/L LaCl3组。此外,各LaCl3组星形胶质细胞的MDA含量均显著高于对照组,且随...     

UVC照射V79细胞后培养液对旁观者细胞影响

目的 探讨ultraviolet C诱导的旁观者效应的可能机制.方法 用辐射强度为9mJ/cm2 UVC照射V 79细胞20 s,分别在第4、8、12h取靶细胞辐照条件培养基(ICM)培养正常细胞24h.四甲基偶氮唑盐法测定细胞存活率;观察染色体畸变;流式细胞仪检测细胞凋亡率.结果 随着ICM时段的往后推移,细胞的存活率逐渐上升,4、8、12h时段ICM培养的细胞存活率分别为(61.5±3.9)％、(78.8±3.3)％、(84.2±4.1)％,与对照组比较,差异均有统计学意义(P＜0.01);染色体畸变率下降,4、8、12 h时段染色体畸变率分别为12.33％、8.67％、5.67％;细胞凋亡率逐渐降低,4、8、12h时段细胞凋亡率分别为(20.78±2.38)％、(13.45 +1.99)％、(10.51±1.53)％,与对照组(3.04±0.39)％比较,差异有统计学意义(P＜0.01).结论 用照射剂量为180mJ/cm2 UVC处理靶细胞后的ICM能够诱导出明显旁观者效应,其表现为细胞凋亡.     

A study of the humoral immunity of mice injected with beryllium chloride]

We studied changes of humoral immunity, such as complement pathway activity, C3 contents and contents of immunoglobulin, in mice injected subcutaneously with BeCl2 or CuCl2 once a week for 12 weeks. Mean body weights of JCL: ICR female mice were approximately 30g in control mice (control group; n = 7), in mice injected with Be (Be group; n = 8) and in mice injected with Cu (Cu group; n = 8). Values of classical complement pathway activity (CH50) were 18.8 +/- 1.4 U per ml, 15.3 +/- 1.8 U per ml and 16.7 +/- 1.3 U per ml in the control group, Be group and Cu group, respectively. The CH50 values of Be and Cu groups were significantly lower than that of the control group (P < 0.01). In contrast, values of alternative complement pathway activity (ACH50) and contents of C3 were almost constant in the three groups. The immunoglobulin content in the Be group tended to increase. The activity of alanine aminotransferase in the Be group was markedly higher than that in the control group (P < 0.05), and the aspartate aminotransferase activity was also high. The CH50 value of mice injected with a small amount of Be once a week over a 12-week period decreased markedly, although either the ACH50 value or C3 content was the same as in the control group. The immunoglobulin content somewhat increased in the Be group. These results suggest the possibility that immune complex is induced by Be.     

MNNG对日本血吸虫成虫培养细胞糖类物质作用

目的研究甲基硝基亚硝基胍(MNNG)对日本血吸虫成虫培养细胞糖类物质动态的影响.方法将日本血吸虫成虫细胞接种于小盖玻片上,置于RPMI-1640含20%小牛血清附加常量抗生素的常规培养基中培养.培养第4 d,细胞被随机分为实验组和对照组.实验组细胞用含3μg/ml MNNG的常规培养基处理48 h,对照组细胞用不含MNNG的常规培养基作相同处理.细胞经彻底清洗后,继续以常规培养基培养3周,然后换用含5%小牛血清的低血清培养基培养.NNNG处理后第1～8周,每周取实验组和对照组细胞进行高碘酸雪夫(PAS)染色和淀粉酶处理后的PAS染色,观察培养细胞内糖类物质的含量及分布变化.取培养第6周的染色细胞,用HPIAS-2000图像分析仪测定细胞内代表糖含量的吸光度,并作统计学分析.结果随着培养时间的延长,对照组培养细胞的着色逐渐变浅,糖含量逐渐减少;实验组细胞的着色则逐渐加深,糖类物质和糖原含量均增加,与对照组比较,差异有统计学意义(P＜0.01).MNNG处理后第5周,实验组细胞着色最深,核质着色型第二类细胞和分裂细胞数目显著增加.结论MNNG诱导后,日本血吸虫成虫培养细胞内糖原和糖类物质含量均明显增加,分裂细胞增多.     

氯化镉对大鼠肾细胞内MAPK基因mRNA表达的影响

目的 观察不同浓度氯化镉(CdCl2)对大鼠肾(NRK)细胞MAPK基因mRNA表达的影响.方法 应用四甲基偶氮唑盐(MTT)比色法检测不同浓度CdCl2(0、2.5、5.0、10.0、20.0和40.0μmol/L)染毒24 h后对NRK细胞存活率的影响;应用带有SYBR Green Ⅰ的实时荧光定量PCR技术观察不同浓度CdCl2(0、2.5、5.0和10.0μmol/L)对NRK细胞内MAPK基因(ERK1/2、p38MAPK、JNK1/2)mRNA表达的影响.结果 以阴性对照组(CdCl2 0μmol/L)NRK细胞存活率为100%,各染毒组(CdCl25.0、10.0、20.0和40.0μmol/L)NRK细胞存活率分别为72.28%、39.95%、15.66%、10.39%,且与对照组之间差异有统计学意义(P<0.01),并存在剂量-效应关系,经CdCl2染毒后,各实验组(CdCl2 2.5、5.0和10.0μmol/L)NRK细胞的ERK1/2、p38MAPK、JNK1/2基因的mRNA的相对表达量均低于阴性对照组(P<0.05或P<0.01).结论 CdCl2可能引起NRK细胞内MAPK基因mRNA的表达水平发生改变.     

氯化铝对原代培养大鼠大脑皮层神经细胞的毒性作用

目的 研究铝对体外培养神经细胞的毒作用,探讨铝的神经毒性和毒作用机制.方法分别应用浓度为10、100、1 000 μmol/L的AlCl3对原代培养大鼠皮层神经细胞染毒24、48 h,检测AlCl3对皮层神经细胞形态的影响,吖啶橙-溴乙锭染色判断皮层神经细胞存活率;Hoechst 33258染色判断皮层神经细胞凋亡.结果 AlCl3可造成皮层神经细胞突起萎缩,细胞胞体增大变圆,细胞数量减少,并且细胞界限不清;同时随着AlCl3浓度增加和染毒时间延长而加重.AlCl3对皮层神经元生长有明显的抑制作用,与对照组相比具有明显时间剂量-反应关系（P＜0.05）;AlCl3可使神经细胞核明显固缩、凝集或断裂,发生典型的凋亡改变,随着染毒时间延长和Al3＋浓度增加,凋亡发生率也明显增加.结论 铝可对原代培养皮层神经细胞产生细胞毒性,可引起细胞结构改变,抑制皮层神经细胞生长,并可诱导细胞凋亡.     

软骨藻酸对原代培养大鼠神经胶质细胞膜的影响

目的 研究软骨藻酸(domoic acid,DA)对原代培养大鼠神经胶质细胞膜的损伤作用.方法 6.4×10-2、6.4×10-3,6.4×10-4 μmol/L的DA作用于原代培养的大鼠神经胶质细胞24 h后,分别测定细胞Na+-K+-ATPase和Ca2+-Mg2+ATPase的活力、细胞膜流动性和通透性的变化.结果 神经胶质细胞经DA处理后,Na+-K+-ATPase和Ca2+-Mg2+-ATPase的活力均明显受到抑制,细胞膜的流动性降低、通透性升高,低、中、高剂量DA染毒组荧光偏振度分别为0.0626±0.0051、0.0685±0.0097、0.0648±0.0086,微黏度分别为0.3154±0.0298、0.3510±0.0571、0.3286±0.0504,与对照组(荧光偏振度为0.0481±0.0069,微黏度为0.2338±0.0372)相比,差异均有统计学意义(P＜0.01).结论 DA能明显损害神经胶质细胞膜的功能,进而可能引发细胞的其他损伤.     

氯化铝致原代培养大鼠海马神经细胞毒性作用

目的 研究铝对体外培养海马神经细胞的毒作用及神经毒性毒作用机制.方法 分别用浓度为10,100,1000 μmol/L的AlCl3对原代培养大鼠海马神经细胞染毒24和48 h,检测AlCl3对海马神经细胞形态影响;吖啶橙-溴化乙锭染色判断海马神经细胞存活率;Hoechst 33258染色判断海马神经细胞凋亡.结果 AlCl3可造成海马神经细胞突起萎缩,细胞胞体增大变圆、细胞数量减少,并且细胞界限不清,并随着AlCl3浓度增加和染毒时间延长而加重,具有明显剂量-反应关系.AlCl3对海马神经元生长有明显的抑制作用,与对照组比较,呈现明显时间-剂量-反应关系(P<0.05).AlCl3可使海马神经细胞胞核明显固缩、凝集或断裂,发生典型的凋亡改变,随着染毒时间延长和A13 浓度增加,凋亡发生率也明显增加.结论 铝可对原代培养海马神经细胞产生细胞毒性,可引起细胞结构改变,抑制海马神经细胞生长,并可诱导细胞凋亡.     

氯化三丁基锡对体外培养小鼠胚胎毒性研究

目的观察氯化三丁基锡的体外培养小鼠胚胎毒性。方法采用全胚胎培养技术,将8.5 d龄昆明种小鼠胚胎置入含有不同浓度氯化三丁基锡的大鼠离心血清中旋转培养48 h,观察体外培养小鼠胚胎生长发育和组织器官形态分化的变化。结果氯化三丁基锡在0.05 mg/L以上时能诱发卵黄囊生长和血管分化不良,胚胎发育异常率增高;高浓度组能诱发脑小、心脏畸形(心小和心包积液)、前肢芽小或无、无后肢芽。结论体外实验条件下,氯化三丁基锡对小鼠胚胎具有胚胎毒性和致畸性。     

Effects of anti-oxidizing vitamins on in vitro cultured porcine neonatal pancreatic islet cells

Oxidative stress may cause severe cellular damage to both allo- and xeno-transplanted islets, additional to islet graft-directed immunity, in diabetic patients. We thus aimed to examine the effects of antioxidants on in vitro culture-maintained, neonatal porcine cell clusters (NPCCs). NPCCs were treated with antioxidants (vitamins D3 and E) by a certain time of their maturation and differentiation process. Insulin recovery showed that both vitamins D3 and E, unlike untreated controls, resulted in preservation of the islet function for significantly long periods of time. Such effects were also confirmed during NPCCs in vitro static incubation with high glucose. Furthermore, morphologic examination of NPCCs demonstrated that at 16 days of cell culture beta-cell clusters were significantly larger and more intact when exposed to the vitamins as compared to controls. According to these preliminary results, because the employed vitamins, known to retain anti-oxidizing properties, seemed to clearly improve NPCCs morphology and function, they may represent a potentially useful tool for islet culture maintenance in the pre-transplant time period.     

Effects of diet and ketones on rat pancreatic lipase in cultured acinar cells

The activity, synthesis rate and mRNA level of pancreatic lipase increase with dietary fat intake. Ketones, intermediates of lipid metabolism, have been proposed to mediate this change. Therefore, we investigated their direct effect on cultured pancreatic acinar cells and examined their possible interactive effects with glucose and dietary fat. beta-Hydroxybutyrate (0.01 to 2 mmol/L) did not affect lipase activity in cells isolated from rats fed a commercial nonpurified (NP) diet and cultured in high glucose (HG, 27.8 mmol/L) or low glucose (LG, 6.9 mmol/L) medium. The effects of ketones were also examined in acinar cells isolated from rats fed purified high fat (HF, 67% of energy from fat) or low fat (LF, 11% of energy from fat) diet. Cellular lipase was significantly higher in cells from HF-fed rats at both 24 and 48 h (264% and 145% of LF values, respectively; P less than 0.0001). beta-Hydroxybutyrate significantly increased (P less than 0.04) lipase activity in LF cells at 48 h but did not affect lipase activity in HF cells. These studies suggest that ketones may be involved in the regulation of pancreatic lipase in rats fed a LF diet, but their role is complex and interactive with dietary carbohydrate and fat.     

Modifying effects of inactivated bovine serum on the acute toxicity of methylmercuric chloride in cells cultured in vitro.

Dynamics of the killing of Ehrlich's murine ascites tumor cells by methylmercuric chloride, MMC, were investigated. Thresholds in the killing action of MMC were observed in the MMC treatment concentration, but not in the MMC treatment time. Inactivated bovine serum protected the E-cells from killing by MMC in vitro. The apparent MMC toxicity was reduced as the serum concentration increased, but remaining partially at high concentrations. Thus the serum increases the threshold for MMC toxicity. It was confirmed that the mode of action, observed as the kinetics of the acute lethality by suspicious substances, could be examined promptly on the mammalian cell level by the present experimental system.     

氟化钠对离体培养大鼠心肌细胞内糖原及琥珀酸脱氢酶的影响

目的探讨氟化物对离体培养大鼠心肌细胞的毒性作用机制。方法应用离体培养心肌细胞模型和细胞化学方法研究不同剂量的氟化钠处理后,细胞搏动或停搏与心肌细胞内糖原的水平及琥珀酸脱氢酶(SDH)活力的变化。结果心肌细胞的停搏率与氟离子(F-)剂量间存在明显的正相关关系(r=0.969、P<0.05),F-的半数停搏物质的量浓度为1.92×10-4mol/L。细胞化学研究及图像分析数据表明,对照组心肌细胞内糖原和SDH反应都呈强阳性,实验组停搏的心肌细胞这2种反应随着F-剂量增加而减弱,呈负相关关系(r分别为-0.917 3,-0.960 3),且不同剂量组间差异都有统计学意义(P<0.05)。结论氟化钠可使心肌细胞内糖原的合成受阻及SDH活力被抑制,导致搏动的心肌细胞因能量供应不足而停搏,呈明显的剂量-反应关系。     

螺内酯对醛固酮诱导的大鼠肾小球系膜细胞氧化应激的影响

目的 观察螺内酯对醛固酮诱导的大鼠肾小球系膜细胞(mesangial cells,MCs)氧化应激的影响,探讨其肾脏保护机制.方法 体外培养大鼠MCs,设正常对照组、醛固酮(10-7 mol/L)刺激组、不同浓度螺内酯(10-7、10-8、10-9mol/L)干预组.以2',7'-二氯双氢荧光素二乙酸酯(2',7'-dichlorofluorescein diacetate,DCFH-DA)为细胞内H2O2的荧光探针标记细胞,采用流式细胞术检测系膜细胞内活性氧(reactive oxygen species,ROS)水平;采用比色法检测培养细胞上清液中丙二醛(malondialdehyde,MDA)的含量和超氧化物歧化酶(superoxide dismutase,SOD)活性.结果 与正常对照组比较,醛固酮刺激系膜细胞48 h后,细胞内ROS水平明显增加,上清液中MDA含量增高、SOD活性下降,差异均有统计学意义(均有P＜0.05).螺内酯干预可明显抑制醛固酮刺激下的系膜细胞的上述反应,差异均有统计学意义(均有P＜0.05),且呈浓度依赖性.结论 螺内酯可呈浓度依赖性地抑制醛固酮诱导的大鼠MCs氧化应激,该作用可能是其肾脏保护机制之一.     

Effects of sodium chloride on bone health

This paper discusses the physiology of sodium effects on calcium metabolism and possible implications of increased salt intake on bone remodelling and bone mass. Osteoporosis is an increasing public health problem affecting more than 200 million of women around the world. The major complications of osteoporosis are fractures, which are frequently associated with high morbidity and mortality. A number of clinical, epidemiological and experimental studies aim at identifying lifestyle factors that may improve bone mass and prevent bone loss. Different nutrients are proposed to play a role in bone development during growth and in the maintenance of bone mass thereafter. However, the importance of sodium intake for bone health has not been elucidated. It is well known that high dietary sodium intake decreases renal calcium reabsorption, which in turn leads to a greater urinary calcium excretion. This effect has been demonstrated in studies in humans of all ages as well as in experimental animals. It is not clear to what extent sodium-induced calcium loss is compensated for by increased intestinal calcium absorption. It is suspected that, if not fully compensated, sustained hypercalciuria due to increased sodium intake may diminish bone mass. Postmenopausal women showed that increased dietary salt may indeed augment bone resorption. Sodium effects on bone mass in various studies are inconsistent and there is still no evidence that increased salt intake is a risk factor in the aetiology of osteoporosis A randomized longitudinal study of different sodium intake in two groups of subject could clarify the role of sodium in bone mass.