间歇运动对老龄小鼠骨骼肌组织自由基代谢的影响

目的 观察间歇游泳训练对老龄小鼠骨骼肌组织自由基代谢的影响.方法 40只健康雌性昆明种小白鼠分为成年对照组、老龄对照组、老龄无负荷间歇运动组、老龄递增负荷间歇运动组、老龄无负荷运动与递增负荷间歇运动交替组.10 w训练结束后48 h在安静状态下处死,行丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化酶(GSH-Px)的测定.结果 老龄无负荷运动组和交替运动组MDA含量[(1.39±0.03),(1.36±0.05) nmol/mgprot]较老龄对照组MDA含量[(1.49±0.08) nmol/mgprot]下降(P＜0.05),无负荷运动组SOD活性[(5.33±0.08) U/mgprot]较老年对照组[(5.23±0.05) U/mgprot]高(P＜0.05),交替运动组SOD活性[(5.39±0.07) U/mgprot]较老年对照组显著增高(P＜0.01).无负荷运动组和交替运动组CAT活性[(1.59±0.06),(1.71±0.07) U/mgprot]较老年对照组[(1.44±0.03) U/mgprot]显著增高(P＜0.01);无负荷运动组CAT活性较负荷运动组高(P＜0.05).负荷运动组GPX活性[(67.93±1.67) U/mgprot]较老年对照组[(66.03±0.58) U/mgprot]高(P＜0.05);无负荷运动组和交替运动组GSH-Px活性[(72.03±2.53),(75.54±4.22) U/mgprot]较老年对照组显著增高(P＜0.01).结论 间歇运动能延缓骨骼肌衰老,但不同形式的间歇运动引起骨骼肌组织自由基代谢的变化不同.     

硒对高氟所致兔血管内皮损伤及动脉硬化影响的病理形态学研究

Objective To study morphological changes of rabbit artery endothelial cell injury and atherosclerosis caused by high fluoride and the role of selenium. Methods Twenty healthy male New Zealand white rabbits, body weight (2.0 ± 0.5)kg, were randomly divided into control group(drinking deionized water, fed basic diet), fluoride group(drinking fluoride 100 mg/L deionized water, fed basic diet), selenium group(drinking selenium 1 mg/L deionized water, fed basic diet), fluoride plus selenium group(drinking fluoride 100 mg/L deionized water, selenium 1 mg/L of deionized water, fed basic diet). The experimental period was 6 months. At 0, 3, 6 months of the experiment, serum fluorine and selenium levels were determined. At the end of the experiment,thoracic aorta was collected to observe its pathology and ultrastructural changes. Results Serum fluoride was significantly higher at the 3rd and the 6th month of experiment(all P ＜ 0.01 ) in fluoride group[ (0.589 ± 0.146),(0.772 ± 0.175)mg/L] and fluoride plus selenium group[ (0.502 ± 0.094), (0.693 ± 0.158)mg/L] than in control group[ (0.174 ± 0.002), (0.208 ± 0.031 )mg/L] and serum fluoride was significantly higher at 6 months than at 3 months(P ＜ 0.05 ) in fluoride group. Serum selenium was significantly higher at the 3rd and the 6th month of experiment (all P ＜ 0.01 ) in selenium group[ (0.252 ± 0.022), (0.319 ± 0.052)mg/L] and fluoride plus selenium group[ (0.239 ±0.016), (0.294 ± 0.018)mg/L] than in control group[(0.135 ± 0.014), (0.167 ± 0.019)mg/L], and serum selenium was significantly higher at the 6th month than at 3rd month of experiment in selenium group(P ＜ 0.05). Endothelial cell apoptosis indices were (4.92 ± 1.32)%, (30.30 ± 6.80)%, (6.57 ± 2.14)% and (14.29 ± 2.99)%, respectively in control group, fluoride group, selenium group and fluoride plus selenium group. Their main effect of fluorine and selenium was statistically significant (F = 106.833,20.082, all P ＜ 0.01 ). There were antagonistic effect between fluoride and selenium(F = 30.402, P ＜ 0.01 ). Pathological changes of rabbit aortic endothelial cells in fluoride group included endothelial with attached fibrin and red blood cells, and structural of the cells changed, with serious vascular injury; in fluoride plus selenium group apoptosis of endothelial cells decreased, with reduced number of attached red blood cells and fibrin, endothelial cell structure normal, the extent and scope of vascular damage significantly reduced. Conclusions Appropriate amount of selenium inhibits the apoptosis of endothelial cells induced by high fluoride, reduces aortic structural damage caused by high fluoride, and maintains the integrity of endothelial cells, thereby antagonizes the vascular damage and atherosclerosis induced by high fluoride.     

氟致体外培养人脐静脉血管内皮细胞损伤的实验观察

目的 观察不同剂量的氟对体外培养人脐静脉血管内皮细胞(HUVEC)的影响.方法 在HUVEC培养液中加入不同剂量的氟化钠(NaF),分别为0(对照)100、400、700、1000、2000 μmol/L,每组设6个复孔,连续培养48 h,收集细胞培养液与细胞.瑞氏-吉姆萨染色观察细胞形态,吖啶橙荧光染色测定细胞凋亡,四唑氮蓝(MT T)比色法检测细胞活性;分光光度法检测细胞培养液中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性、丙二醛(MDA)水平及诱导型一氧化氮合酶(iNOS)、内皮型一氧化氮合酶(eNOS)活性;RT-PCR法检测细胞iNOS mRNA和eNOS mRNA表达水平;双抗体夹心ELISA法检测细胞培养液中细胞黏附因子(ICAM-1)、血管黏附因子(VCAM-1)水平.结果 随染氟剂量增加,HUVEC细胞数量减少,结构改变;400～2000μmol/L NaF组SOD活性[(6.627±0.213)、(6.668±0.152)、(5.935±0.122)、(4.755±0.182)kU/L]较对照组[(7.457±0.398)kU/L]降低(P＜0.05或＜0.01),GSH-Px活性[(481.284±43.785)、(492.223±16.474)、(382.762±25.167)、(293.687±24.881)kU/L]较对照组[(585.078±47.323)kU/L]降低(P＜0.05或＜0.01),MDA水平[(0.609±0.011)、(0.646±0.016)、(0.852±0.013)、(1.188±0.045)nmol/L]较对照组[(0.512±0.027)nmol/L]升高(P＜0.05或＜0.01);iNOS活性[(3.604±0.115)、(3.615±0.075)、(3.848±0.103)、(4.275±0.079)kU/L]较对照组[(2.798±0.136)kU/L]增强(P均＜0.01),iNOS mRNA表达增强,eNOS活性[(5.539±0.079)、(5.503±0.064)、(5.226±0.142)、(4.809±0.107)kU/L]较对照组[(5.996±0.155)kU/L]减弱(P＜0.05或＜0.01),eNOSmRNA表达减弱;ICAM-1水平[(0.852±0.102)、(0.886±0.061)、(0.961±0.158)、(1.418±0.167)μg/L]较对照组[(0.687±0.046)μg/L]升高(P＜0.05或＜0.01),VCAM-1水平[(2.719±0.197)、(2.946±0.167)、(3.173±0.225)、(3.613±0.153)μg/L]较对照组[(2.375±0.067)μg/L]升高(P均＜0.01).结论 高剂量氟降低抗氧化酶活性,使一氧化氮代谢紊乱,细胞因子异常表达,以此抑制血管内皮细胞生长、结构改变并致细胞凋亡,为高氟致血管内皮损伤的重要因素.

Abstract：

Objective To study the effect of different concentrations of fluoride on cultured human umbilical vein vascular endothelial cells(HUVEC). Methods Different doses of sodium fluoride (NaF) were added to HUVEC culture medium, fluoride concentrations were 0(control), 100,400,700,1000,2000 μmol/L, respectively,6 re-set hole in each group. After continuous culture for 48 h, cells and culture medium were collected. Cell morphology was studied by Wright-Giemsa staining; cells apoptosis was determined by acridine orange fluorescence staining; cell activity was measured by methyl thiazolyl tetrazolium (MTT) assay; superoxide dismutase (SOD),glutathione peroxidase(GSH-Px) activity, malonaldehyde(MDA) content, induced nitricoxide synthase(iNOS), and endothelia nitricoxide synthase(eNOS) activity in cell culture medium were determined by spectrophotometry; cell iNOS mRNA and eNOS mRNA expression were detected by RT-PCR; intercellular adhesion molecule-1 (ICAM-1)and vascular cell adhesion molecule-1 (VCAM-1) levels were detected by double antibody sandwich ELISA method.Results With increased dose of fluoride, HUVEC cells decreased, the structure changed. In 400 - 2000 μmol/L group, the SOD activity[(6.627 ± 0.213), (6.668 ± 0.152), (5.935 ± 0.122), (4.755 ± 0.182)kU/L] was lower than those of the control group[(7.457 ± 0.398)kU/L, P ＜ 0.05 or ＜ 0.01], GSH-Px activity[(481.284 ± 43.785),(492.223 ± 16.474), (382.762 ± 25.167), (293.687 ± 24.881 )kU/L] was also lower than those of the control group [(585.078 ± 47.323)kU/L, P ＜ 0.05 or ＜ 0.01], MDA level[(0.609 ± 0.011 ), (0.646 ± 0.016), (0.852 ± 0.013),(1.188 ± 0.045)nmol/L] was higher than those of the control group[(0.512 ± 0.027)nmol/L, P ＜ 0.05 or ＜ 0.01];iNOS activity[(3.604 ± 0.115), (3.615 ± 0.075), (3.848 ± 0.103), (4.275 ± 0.079)kU/L] also was higher than those of the control group[(2.798 ± 0. 136)kU/L, all P ＜ 0.01], iNOS mRNA expression increased, eNOS activity [(5.539 ± 0.079), (5.503 ± 0.064), (5.226 ± 0.142), (4.809 ± 0. 107)kU/L] decreased compared to those of control group[(5.996 ± 0.155)kU/L, P ＜ 0.05 or ＜ 0.01], eNOS mRNA expression decreased; ICAM-1 levels [(0.852 ± 0. 102), (0.886 ± 0.061 ), (0.961 ± 0.158), (1.418 ± 0. 167)μg/L] increased compared to those of the control group[(0.687 ± 0.046)μg/L, P ＜ 0.05 or ＜ 0.01], VCAM-1 levels[(2.719 ± 0.197), (2.946 ± 0.167),(3.173 ± 0.225 ), (3.613 ± 0. 153 ) μg/L] was higher than those of the control group [(2.375 ± 0.067 ) μg/L, all P ＜0.01]. Conclusions High concentrations of fluoride reduce the activity of antioxidant enzymes, which leads to metabolic disorders of nitric oxide and abnormal cytokines expression, thereby inhibiting vascular endothelial cell growth, structural change and induced apoptosis. This is an important factor in high fluoride-induced vascular endothelial injury.     

燃煤型氟中毒大鼠脑组织神经型尼古丁受体mRNA及蛋白表达水平改变

目的 观察燃煤型氟中毒大鼠学习记忆能力变化,测定大鼠脑组织神经型尼古丁受体(nAChR)mRNA和蛋白表达水平,探讨大鼠学习记忆能力改变的发生机制.方法 健康SD大鼠24只,体质量100～120 g,按体质量随机分为3组,每组8只.对照组饲以常规饲料,低氟组和高氟组以燃煤型氟中毒重病区燃煤烘烤的当地玉米为主要饲料(含氟量分别为11.30、104.20 mg/kg)来复制慢性氟中毒大鼠模型,染氟时间为6个月.染氟结束后,用Morris水迷宫方法检测大鼠行为学变化,处死动物取脑,用匀浆-氟离子选择电极法测定脑组织含氟量,实时荧光定量PCR法检测nAChR mRNA水平,蛋白印迹法测定nAChR蛋白表达水平.结果 低氟组和高氟组大鼠逃避潜伏期时间[(12.42±8.03)、(17.48±8.05)s]较对照组[(7.04±3.29)s]显著延长(P均<0.05),高氟组第7天穿过平台次数[(1.62±0.87)次]和逗留平台象限时间[(16.70±5.02)s]较对照组[(3.53±1.67)次、(23.33±5.35)s]降低(P均<0.05).低氟组和高氟组大鼠脑组织含氟量[(1.14±0.04)、(1.79±0.04)mg/kg]显著高于对照组[(0.52±0.05)mg/kg,P均<0.05],且高氟组大鼠脑组织含氟量高于低氟组(P<0.05).高氟组大鼠脑组织nAChR α3、α4、α7亚单位mRNA水平(1.51±0.20、1.45±0.06、1.63±0.08)较对照组(1.79±0.11、1.66±0.14、1.83±0.06)显著降低(P均<0.05),而低氟组(1.65±0.17、1.59±0.09、1.71±0.03)与对照组比较无明显改变(P均>0.05).低氟组和高氟组大鼠脑组织nAChR α3、α4、α7亚单位蛋白表达水平(0.58±0.13、0.16±0.03、1.41±0.38和0.56±0.23、0.08±0.02、0.51±0.16)较对照组(1.48±0.42、0.57±0.21、2.56±0.26)显著降低(P<0.05或<0.01).结论 燃煤型氟中毒大鼠学习记忆能力降低可能与脑组织nAChR蛋白表达及mRNA水平降低有关,nAChR表达改变可能是引起动物学习记忆能力降低的主要机制.

Abstract：

Objective To observe the learning and memory changes in coal-burning type of fluorosis rats, detect the expressions of neuronal nicotinic acetylcholine receptor(nAChR) at mRNA and protein levels in rat brains and to reveal the mechanism of changed learning and memory ability. Methods Twenty-four healthy SD rats, weighting 100 - 120 g, were randomly divided into three groups(8 in each). Control group was fed with normal diet, and low- and high-dose fluoride groups were fed with corn polluted with high fluoride (fluoride were 11.30,104.20 mg/kg, respectively) during drying processes with local burning-coal from the areas of endemic fluorosis to established rat model of chronic fluorosis. After exposed to fluoride for 6 months, behavioral changes were measured by Morris water maze. Animals were sacrificed, the brain was taken, after homogenizing the fluoride content of brain tissue was determined by fluoride ion selective electrode. The α3, α4 and α7 nAChR subunits at mRNA and protein levels were analyzed by real-time PCR and Western blotting, respectively. Results For rats in low- and high-fluoride groups, the escape latency time[(12.42 ± 8.03),(17.48 ± 8.05)s] was significantly longer than that in the control[(7.04 ± 3.29)s, all P< 0.05]. For rats in high-fluoride group, the numbers of crossing the platforms (1.62 ± 0.87) and the time of staying at the platforms[(16.70 ± 5.02)s] were significantly decreased as compared to that of control[3.53 ± 1.67, (23.33 ± 5.35)s, all P < 0.05]. The fluoride content in rat brain tissue in low- or high-fluoride groups [(1.14 ± 0.04), (1.79 ± 0.04)mg/kg] was significantly higher than that of control [ (0.52 ± 0.05) mg/kg, all P < 0.05]; in addition, the amount of fluoride in brain tissue of high-fluoride group was significantly higher than that of low-fluoride group(P < 0.05). In high-fluoride group, the mRNA expressions of α3, α4 and α7 nAChR subunits in rat brains(1.51 ± 0.20,1.45 ± 0.06,1.63 ± 0.08) were significantly lower as compared to controls (1.79 ± 0.11,1.66 ± 0.14,1.83 ± 0.06, all P< 0.05); whereas there were no significant changes in mRNA levels of these receptor subunits of the rat brains between low-fluoride group(1.65 ± 0.17,1.59 ± 0.09,1.71 ± 0.03) and controls (all P > 0.05). Furthermore, the protein levels of α3, α4 and α7 nAChR subunits in rat brains of highfluoride group(0.58 ± 0.13,0.16 ± 0.03,1.41 ± 0.38) and low-fluoride group(0.56 ± 0.23,0.08 ± 0.02,0.51 ± 0.16) were significantly lower than those of controls( 1.48 ± 0.42,0.57 ± 0.21,2.56 ± 0.26, P<0.05 or < 0.01). Conclusions Decreased ability of learning and memory in coal-burning type of fluorosis rats may be associated with declined expressions of nAChR at proteins and mRNA levels, which might be the main mechanism of the behavior change.     

黄绿青霉素对低硒低蛋白大鼠心肌损伤的初步观察

目的 观察黄绿青霉素(CIT)对低硒低蛋白大鼠心肌损伤的特点.方法 40只4周龄Wistar大鼠,雌雄符半,体质量60～80 g,按2×2析因设计随机分为常硒常蛋白无毒素组、常硒常蛋白加毒素组、低硒低蛋白无毒素组和低硒低蛋白加毒素组(将低硒低蛋白合为一种因素考虑),每组10只.分别采用常硒常蛋白和低硒低蛋白饲料喂养大鼠至第10周后,加毒素组大鼠饲料中投予CIT(5 mg·kg-1·d-1)继续喂养至第16周.观察各组大鼠的毛色、摄食、体质量增长情况,计算心脏质量指数,观察心肌病理变化,检测血清硒、白蛋白水平、肌酸激酶(CK)和谷胱甘肽过氧化物酶(GSH-Px)活性以及心肌超氧化物歧化酶(SOD)活性.结果 硒、蛋白和CIT对大鼠体质量、血清硒、白蛋白水平、心脏质量指数、血清CK、GSH-Px活性和心肌SOD活性的影响不存在交互作用(F值分别为0.000、1.210、0.625、0.981、2.785、0.074、0.001,P均>0.05);硒、蛋白对大鼠血清硒、白蛋白水平、心脏质量指数和血清GSH-Px活性的主效应有统计学意义(F值分别为507.698、87.734、4.201、109.389,P均<0.05);CIT对大鼠体质量、血清硒、白蛋白水平、心脏质量指数、血清CK活性的主效应有统计学意义(F值分别为10.929、4.371、26.108、24.844、4.439,P均<0.05).低硒低蛋白两组的血清硒水平[(70.4±40.0)、(87.7 ±59.6)μg/L]低于常硒常蛋A两组[(446.1±74.8)、(502.1±39.2)μg/L,P均<0.05];低硒低蛋白两组的血清白蛋白水平[(34.36±1.28)、(33.38±2.48)g/L]低于常硒常蛋白两组[(40.69±1.30)、(38.71±2.15)g/L,P均<0.05];相同硒和蛋白水平下,加毒素组的心脏质量指数[(4.14±0.36)×10-3、(4.39 ±0.53)×10-3]高于无毒素组[(3.56±0.26)×10-3、(3.80±0.28)×10-3,P均<0.05];低硒低蛋白加毒素组的血清CK活性[(2.54 ±0.56)kU/L]低于低硒低蛋白无毒素组[(3.37±0.67)kU/L,P<0.05].低硒低蛋白两组的血清GSH-Px活性>(408.1±412.6)、(510.5 ±392.0)U/L[低于常硒常蛋白两组[(1667.8±102.2)、(1731.5±144.4)U/L,P均<0.05].电镜结果显示,常硒常蛋白加毒素组大鼠部分心肌细胞闰盘断裂,各带连接断裂,部分区域心肌细胞有溶解现象,有水肿表现;低硒低蛋白无毒素组大鼠心肌细胞膜结构改变不明显,核周围肌丝结构消失,可见大量絮状物质沉积;低硒低蛋白加毒素组大鼠心肌细胞肌节各带结构不很清晰,核旁线粒休嵴轻度疏松,偶见空泡变,大量弥漫性肌质网扩张.结论 CIT是诱导大鼠心肌细胞损伤的主要因素,低硒低蛋白加重病变,但独立致病作用较弱.

Abstract：

Objective To ohserve the rat myocardial damage induced by citreoviridin(CIT)in the status of combined selenium and protein deficiency.Methods According to 2×2 factorial design,forty 4-week-old healthy Wistar rats were randomly divided into four groups.i.e.combined selenium and protein adequate with no CIT and with some CIT groups(Se+Pro+CIT-.Se+Pro+CiT+),combined selenium and protein deficiency with no CIT and with some CIT groups(Se-Pro-CIT-,Se-Pro-CIT+).The numbers of male and female were fifty-fifty.Theserats were fed with combined selenium and protein adequate and combined selenium and protein deficiency fodder until the 16th week. Cardiac toxicity of CIT was evaluated by general state of health, heart weight index, myocardial pathological change, the levels of selenium and the activities of glutathion peroxidase (GSH-Px) and creatine kinase (CK) in serum, and the activity of superoxide dismutase(SOD) of myocardium. Results The interaction effects of combined selenium and protein deficiency and adequate CIT on body weight, serum levels of selenium and albumin, heart weight index, the activities of CK and GSH-Px in serum and SOD of myocardium were statistically not significant(F= 0.000, 1.210, 0.625, 0.981, 2.785, 0.074, 0.001, all P> 0.05). The main effects of combined selenium and protein on the levels of serum selenium and albumin, heart weight index and the activity of GSH-Px in serum were statistically significant(F = 507.698, 87.734, 4.201, 109.389, all P < 0.05). The main effects of CIT on body weight, the levels of serum selenium and albumin, heart weight index and the activity of CK in serum were statistically significant(F = 10.929, 4.371, 26.108, 24.844, 4.439, all P < 0.05). The mean levels of serum selenium of Se-Pro- groups [(70.4 ± 40.0), (87.7 ± 59.6 )μg/L] were lower than those of Se+Pro+ groups [(446.1 ± 74.8),(502.1 ± 39.2)μg/L, all P < 0.05]. The mean levels of serum albumin of Se-Pro- groups [(34.36 ± 1.28 ), (33.38 ±2.48)g/L] were lower than those of Se+Pro+ groups[(40.69 ± 1.30), (38.71 ± 2.15)g/L, all P < 0.05]. The mean levels of heart weight index of CIT+ groups[(4.14 ± 0.36) × 10-3, (4.39 ± 0.53) x 10-3] were higher than those of CIT-groups[(3.56 ± 0.26) x 10-3, (3.80 ± 0.28) x 10-3, all P < 0.05] respectively at the same levels of selenium and protein. The mean levels of CK in serum of Se-Pro-CIT+ group[(2.54 ± 0.56)kU/L] was lower than that of Se-Pro-CIT- group [(3.37 ± 0.67 )kU/L, P < 0.05]. The mean levels of activity of GSH-Px in serum of Se-Progroups[(408.1 ± 412.6), (510.5 ± 392.0)U/L] were lower than those of Se+Pro+ groups[(1667.8 ± 102.2),(1731.5 ± 144.4)U/L, all P < 0.05]. In Se+Pro+CIT+ group, there was part of intercalary disc of cardiac myocytes fragmented;the conjunctions between myoeytes were broken;in some region, cardiac myocytes became edematous,even dissolved. In Se-Pro-CIT- group, the change of cardiac myocytes membrane structures was not obvious;filament structure was disappeared around nucleus;deposition of mass floccule could be seen. In Se-Pro-CIT+ group,the structure of sarcomeres was not obvious;mitochondrial cristae was loosened;cavities in myocytes could be seen occasionally;there were lots of disseminated sareoplasmic reticulum extending. Conclusions .CIT is the main risk factor in inducing myocardial damage. The deficiency of combined selenium and protein can aggravate the damage,but its independent pathogenic effect is weak.     

神经调节辅助通气对急性呼吸窘迫综合征兔呼吸机相关性膈肌功能障碍的影响

目的 探讨神经调节辅助通气(NAVA)对ARDS呼吸机相关性膈肌功能障碍(VIDD)的预防作用.方法 将20只成年新西兰大白兔按随机数字表法分为对照组、容量控制通气组(VC组)、压力支持通气组(PSV组)和NAVA通气组(NAVA组),每组5只.VC、PSV及NAVA组在机械通气4 h后取膈肌标本,对照组麻醉后立即取膈肌标本.测定各组膈肌中丙二醛、超氧化物歧化酶(SOD)以及还原型谷胱甘肽(GSH)含量,观察各组膈肌纤维病理结构的改变.结果 (1)丙二醛:NAVA组膈肌中丙二醛含量为(0.28±0.19)nmol/mg,与对照组的(0.15±0.06)nmol/mg、PSV组的(0.30±0.11)nmol/mg比较,差异无统计学意义(F=2.730,P＞0.05);VC组膈肌中丙二醛含量为(0.40±0.16)nmol/mg,明显高于对照组(P＜0.05).(2)SOD:NAVA组膈肌中SOD含量为(94±9)U/mg,与对照组的(111±12)U/mg、PSV组的(93±4)U/mg比较,差异无统计学意义(F=4.422,P＞0.05);VC组膈肌中SOD含量为(80±21)U/mg,明显低于对照组(P＜0.05).(3)GSH:NAVA组膈肌中丙二醛含量为(5.6±1.0)mg/g,与对照组的(5.3±1.0)mg/g、PSV组的(4.5±1.2)mg/g比较,差异无统计学意义(F=3.001,P＞0.05);VC组膈肌中GSH含量为(3.3±1.7)mg/g,明显低于对照组(P＜0.05).(4)光镜观察:VC组出现肌纤维变性、坏死,部分肌纤维萎缩;NAVA、PSV组以及对照组肌纤维形态基本正常.(5)电镜观察:VC组肌原纤维断裂,线粒体肿胀;NAVA组、PSV组以及对照组超微结构无明显异常.(6)膈肌纤维横截面积:NAVA组平均肌纤维横截面积(像素)为2573±278,与对照组的3070+175、PSV组的2508±670比较,差异无统计学意义(F=1.775,P＞0.05);VC组Ⅱ型肌纤维横截面积为2210±971,明显低于对照组的3477±187(P＜0.05).结论 与控制通气相比较,NAVA可减轻ARDS膈肌氧化应激、膈肌萎缩和膈肌结构损伤,NAVA较控制通气更能预防VIDD.

Abstract：

Objective To evaluate the effect of neurally adjusted ventilatory assist (NAVA) on prevention of ventilator-induced diaphragmatic dysfunction (VIDD) in ARDS rabbits.Methods Twenty New Zealand white rabbits were randomly divided into 4 groups: ( 1 ) control group ( n = 5 ); ( 2 ) Volume control (VC) group ( n = 5 ); ( 3 ) Pressure support ( PSV ) group ( n = 5 ); (4) NAVA group ( n = 5 ).In VC, PSV and NAVA groups, the rabbits were killed and the diaphragm was removed after 4 hours of ventilation.Animals in the control group were not mechanically ventilated, and the diaphragm was also removed immediately after anesthetizing.In all rabbits, malondialdehyde ( MDA), superoxide disrmutase (SOD) and glutathione(GSH) of diaphragm were measured.Structure of diaphragm was observed by light microscope, electron microscope, constituent ratio and mean cross-sectional area (CSA) of diaphragm fiber.Results (1)MDA: Compared with the control [(0.15 ±0.06)nmol/mg], PSV group[(0.30 ±0.11)nmol/mg], there was no significant difference in MDA of diaphragm in NAVA group [( 0.28 ± 0.19 )nmol/mg] (F = 2.730, P ＞ 0.05).MDA in VC group [(0.40 ±0.16)nmol/mg] was significantly higher than the control group (P＜0.05).(2) SOD: Compared with control [( 111 ± 12) U/mg], PSV group [(93 ± 4) U/mg], there was no significant difference in SOD of diaphragm in NAVA group [( 94 ± 9 )U/mg] (F=4.422,P ＞0.05).SOD in VC group [(80 ±21 )U/mg] was significantly lower than the control group(P ＜0.05).(3)GSH: Compared with control [(5.3 ± 1.0)mg/g] and PSV group [(4.5 ±1.2)mg/g], there was no significant difference in GSH of diaphragm in NAVA group [(5.6 ± 1.0) mg/g](F =3.001 ,P ＞ 0.05 ).GSH in VC group [(3.3 ± 1.7)mg/g] is significantly lower than control and NAVA groups ( P ＜ 0.05 ).( 4 ) Light microscope: In VC group, many changes were observed in the muscle, such as myofibrosis, necrosis, and some of muscle fibers became atrophy, but these were no obvious changes of pathological structure in control, PSV or NAVA groups.(5)Electron microscope: In control, PSV and NAVA groups, the ultrastructure of diaphragm was normal Different from the above 3 groups, some abnormal ultrastructure was observed in VC group, including disrupted myofibrils, swollen mitochondria.(6)CSA of diaphragm fiber: Compared with control and PSV group, there was no significant difference in CSA of diaphragm fiber in NAVA group ( P ＞ 0.05 ); The CSA of type Ⅱ fibers in VC group was markedly lower than control group ( P ＜ 0.05 ) .Conclusions Compared with volume control ventilation, NAVA may mitigate diaphragmatic oxidative stress, atrophy and injury, and prevent VIDD better than VC.     

氟对雄性大鼠睾丸组织金属元素水平的影响

目的 探讨慢性氟中毒对大鼠睾丸组织金属元素水平的影响,为氟的生殖毒性研究提供一定实验依据.方法 健康雄性Wistar大鼠32只,体质量150～180 g,按体质量随机分为4组,生理盐水(对照)组、低、中、高氟组(100、200、300 mg-kg-1·d-1NaF),每组8只,灌胃染毒90 d,每天称体质量.染氟结束次日,颈椎脱位法处死大鼠,摘取睾丸组织,原子吸收分光光度计测定睾丸组织中会属元素钙(Ca)、铁(Fe)、锌(Zn)、铜(Cu)和镁(Mg)水平.结果 染氟第30天大鼠体质量组间比较,差异有统计学意义(F=3.884,P<0.05),其中低、中氟组[(235.00±14.56)、(235.44±24.99)g]高于高氟组[(206.00±18.16)g,P均<0.05];第0、60、90天大鼠体质量组间比较,差异无统计学意义(F值分别为0.501、0.578、1.893,P均>0.05).4组大鼠睾丸组织Ca、Zn和Mg组间比较,差异有统计学意义(F值分别为6.630、6.844、5.333,P均<0.05),其中元素Ca低氟组[(56.15±4.21)mg/kg]较对照组[(77.57±6.66)mg/kg]降低,元素Zn低、中、高氟组[(4.80±0.55)、(4.56±0.33)、(5.46±0.79)mg/kg]较对照组[(7.16±0.28)mg/kg]降低,元素Mg高氟组[(32.44±1.53)mg/kg]较对照组[(42.54±8.07)mg/kg]降低(P均<0.05);4组大鼠睾丸组织Fe和Cu组间比较,差异无统计学意义(F值分别为1.324、0.207,P均>0.05).结论 慢性氟中毒可通过影响大鼠睾丸组织金属元素水平损害大鼠生殖系统.

Abstract：

Objective To probe into the effects of fluoride on metal elements in the testis tissue of male rats, and provide experimental basis to further research for reproductive toxicity of fluoride. Methods Thirty-two healthy male Wistar rats, weighting 150 - 180 g, were randomly divided into 4 groups, normal sodium(control) by intragastrie administration for 90 days, and body weight was observed daily. After the last intragastric administration, all rats were killed by cervical dislocation. The contents of calcium(Ca), ferri(Fe), zincum(Zn),cuprum(Cu ) and magnesium(Mg) in the testis tissue were measured by atomic absorption speetrophotometry.Results After 30 days exposure, the difference of body weight between groups was statistically significant(F=3.884, P < 0.05). The body weight in low- and medium-dose groups[(235.00 :t: 14.56), (235.44 ± 24.99)g] were significant increased than high-dose group[(206.00 ± 18.16)g, all P < 0.05]. There was no significant difference of body weight between the groups at 0, 60 and 90 days(F = 0.501, 0.578, 1.893, all P > 0.05). The difference of Ca, Zn and Mg levels among four groups was statistically significant(F = 6.630, 6.844, 5.333, all P < 0.05). The content of Ca of the low-dose group[(56.15 + 4.21 )mg/kg] decreased than that of the control group[(77.57 ± 6.66)mg/kg, P < 0.05];the content of Zn of the low-, medium- and high-dose groups[(4.80 ± 0.55), (4.56 ± 0.33),(5.46 ± 0.79 )mg/kg] deceased than that of the control group [(7.16 ± 0.28 )mg/kg, all P < 0.05];the content of Mg of the high-dose group [(32.44 ± 1.53 ) mg/kg] decreased than that of the control group [(42.54 ± 8.07 ) mg/kg,all P < 0.05]. The difference of testis Fe and Cu between four groups was not statistically significant(F = 1.324,0.207, all P > 0.05). Conclusion Chronic fluorosis can affect the levels of metal elements in rat testis and damage the reproductive system.     

维持性血液透析患者外周血单个核细胞核因子κB活性与微炎症、氧化应激状态及心血管疾病的关系

目的:探讨维持性血液透析(MHD)患者外周血单个核细胞(PBMC)核因子κB (NF-κB)活性与微炎症、氧化应激状态及心血管疾病(CVD)的关系. 方法:选取MHD治疗3个月以上的患者(32例),以体检健康者(12例)为对照组.采用ELISA法检测受试者PBMC的NF-κB活性,比色法检测血清总抗氧化能力(TAOC)及丙二醛(MDA).Pearson相关和线性回归分析PBMC的NF-κB活性与其他指标的相关性.二分类Logistic回归分析NF-κB活性与CVD的关系. 结果:MHD患者PBMC的NF-κB活性[(1 142.4±413.0)ng/mg核蛋白vs(208.3±39.5) ng/mg核蛋白,P＜0.05]、血清高敏C反应蛋白(hsCRP)(3.2 mg/L vs0.5 mg/L,P＜0.05)、TAOC[ (21.9±6.6)U/ml vs (15.7±2.3)U/ml,P＜0.05]和MDA[ (6.80±0.86) nmol/ml vs (3.89±0.51) nmol/ml,P＜0.05]皆显著高于对照组.单次HD后MHD患者PBMC的NF-κB活性显著升高[(2 076.5±690.1)ng/mg核蛋白vs(1 142.2 ±413.0)ng/mg核蛋白,P＜0.05],TAOC显著降低[(13.6±5.0) U/ml vs(21.9±6.6)U/ml,P＜0.05].Pearson相关分析显示PBMC的NF-κB活性与白细胞计数(r=0.454,P＜0.05)、血清hsCRP(r =0.590,P＜0.05)及MDA(r=0.390,P＜0.05)呈正相关.线性回归分析显示白细胞计数(β=0.338,P＜0.05)、血清hsCRP(β =0.440,P＜0.05)及MDA(β=0.319,P＜0.05)皆与PBMC的NF-κB活性独立相关.Logistic回归分析显示PBMC的NF-κB活性升高(＞1 170.0 ng/mg核蛋白)是CVD的独立危险因素(OR=8.47,P＜0.05). 结论:MHD患者PBMC的NF-κB活性显著升高,且与微炎症、氧化应激状态及CVD相关,可作为患者的炎症标志物.     

低剂量亚慢性砷染毒家兔血清酶和生物化学指标的变化

目的 观察低剂量亚慢性砷染毒家兔在染毒不同时期血清酶和生物化学指标的变化,为筛选有意义的砷中毒早期诊断血液学指标提供依据.方法 成年家兔12只,体质量2.0～3.5kg,按体质量随机分为4组,每组3只,分别饮用含亚砷酸钠0(对照)、0.01、0.05、0.25 mg/L的水.染毒8周和12周后,采用SYSMEX-180型全自动生化分析仪测定各组家兔血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)和γ-谷氨酰基转移酶(γ-GT)的活性以及总蛋白、白蛋白、球蛋白和白蛋白/球蛋白比值(简称白球比).结果 染毒家兔0.05 mg/L剂量组第12周ALT水平[(60.00±4.14)U/L]较同期对照组[(41.50±2.12)U/L]升高(P＜0.05);0.25 mg/L剂量组第8周、第12周AST水平[(46.50±3.21)、(52.33±3.81)U/L]较同期对照组[(21.33±3.53)、(29.50±3.23)U/L]升高(P均＜0.05);0.05 mg/L剂量组和0.25 mg/L剂量组第12周ALP水平[(78.68±4.85)、(103.00±7.83)U/L]较同期对照组[(45.50±5.50)U/L]升高(P均＜0.05);0.05mg/L剂量组第12周γ-GT水平[(19.33±7.50)U/L]较同期对照组[(8.50±3.53)U/L]升高(P＜0.05).各剂量组第8周和第12周的血清总蛋白、白蛋白、球蛋白水平和白球比与同期对照组比较,差异无统计学意义(F值分别为0.77、0.02、0.16、3.14和0.51、0.29、0.41、0.52,P均＞0.05).结论 0.05 mg/L及以上剂量亚慢性砷染毒主要对肝脏有一定损伤.在肝脏的相关血清酶学中,AST是较为早期的反映砷中毒肝脏损伤的敏感指标.

Abstract：

Objective To observe the sub-chronic effects of low doses of arsenic poisoning in rabbits exposed to different periods on some of the serum enzymes and biochemical indicators, and to provide the basis for screening of meaningful hematologic indicators for early diagnosis of arsenic poisoning. Methods Twelve adult rabbits,weighing 2.0 - 3.5 kg, were randomly divided into four groups, 3 in each group, and they were fed with drinking water containing sodium arsenite 0(control),0.01,0.05,0.25 mg/L, respectively. Serum alanine aminotransferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP), γ-glutamyl transacylase (y-GT), total protein(TP), albumin(ALB), globulin(GLP), and ALB/GLP of rabbit were measured by SYSMEX-180 automated biochemistry analyzer after 8 weeks and 12 weeks exposure. Results The results showed that ALT in 0.05 mg/Lgroup of 12 week[(60.00 ± 4.14)U/L]increased significantly compared with the control[(41.50 ± 2.12)U/L, P ＜0.05];AST in 0.25 mg/L group of 8 week and 12 week[(46.50 ± 3.21 ), (52.33 ± 3.81 )U/L]increased significantly compared with the control[(21.33 ± 3.53), (29.50 ± 3.23 )U/L, all P ＜ 0.05];ALP in 0.05 mg/L and 0.25 mg/L group of 12 week [(78.68 ± 4.85 ), ( 103.00 ± 7.83 ) U / L]increased significantly compared with the control [(45.50 ± 5.50)U/L, all P ＜ 0.05];γ-GT in 0.05 mg/L group of 12 week[(19.33 ± 7.50)U/L]increased significantly compared with the contro1[(8.50 ± 3.53)U/L, P＜ 0.05]. TP, ALB, GLP, ALB/GLP of different groups of 8 week and 12 week were not significantly different statistically(F= 0.77,0.02,0.16,3.14 and 0.51,0.29,0.41,0.52, all P ＞ 0.05). Conclusions Zero point zero five mg/L and higher doses of sub-chronic arsenic exposure has some major damage to the liver. Compared with other serum enzymes and the biochemical indexes, serum AST is a early sensitive indicator of liver injury of the arsenic poisoning.     

慢性氟中毒对大鼠脑组织Phospho-Elk-1表达的影响

目的 观察慢性氟中毒大鼠脑组织中细胞外调节蛋白激酶(ERK1/2)信号转导通路下游作用底物三元复合物因子Phospho-Elk-1的表达和分布,探讨慢性氟中毒所致学习记忆损害的发生机制.方法 SD 大鼠72只,体质量100～120 g,按体质量随机分为3组,每组24只,雌雄各半.对照组饮用自来水(含氟量<0.5 mg/L),低氟组和高氟组饮用加入氟化钠的自来水(P质量浓度分别为5.0、50.0 mg/L).6个月后,称取大鼠体质量,观察氟斑牙发生情况,用氟离子选择电极法检测大鼠尿氟及骨氟;用Morris水迷宫方法的定向航行实验检测大鼠学习能力,空间探索实验检测大鼠记忆能力;用免疫组织化学方法检测大鼠脑组织中Phospho-Elk-1在蛋白水平的表达和分布.结果 低氟组和高氟组大鼠体质量[(449.2±77.1)、(312.8 ±89.7)g]较对照组[(635.5±76.2)g]显著下降(P均<0.05),出现不同程度氟斑牙(x2=7.83,P<0.05),尿氟[(2.56±0.91)、(5.73±3.14)mg/L]及骨氟[(709.2±37.4)、(1306.3 ±102.4)mg/kg]较对照组[(0.92±0.30)mg/L、(348.5 ±89.2)mg/kg]明显升高(P均<0.05).低氟组和高氟组大鼠逃避潜伏期[(7.4±4.1)、(12.2±5.7)s]较对照组[(4.8±2.7)s]明显延长(P均<0.05),第1次穿越平台区时同[(4.18±1.10)、(5.89±0.56)s]较对照组[(1.17±0.75)s]显著延长(P均<0.05),均以高氟组尤为明显(P均<0.05).低氟组和高氟组大鼠海马CA1区(167.4±8.3、163.2±9.4)、CA2区(175.7±5.0、183.3±4.2)、CA3区(165.2±11.6、162.9±4.4)、CA4 区(168.7±6.9、169.5±5.3)、齿状回(185.2 ±4.0、193.1±6.1)及尾壳核(181.4±3.8、179.8±5.5)神经细胞Phospho-Elk-1表达水平较对照组(142.4±8.1、144.9±8.4、143.6±5.8、116.8±9.1、140.2±7.8、163.1±13.1)显著增加(P均<0.05).结论 慢性氟中毒可引起大鼠脑组织海马及尾壳核区域Pbospho-Elk-1表达水平升高,这种改变可能与大鼠学习记忆能力下降机制有一定关系.

Abstract：

Objective To investigate the expression and distribution of the downstream substrate of extracellular regulated protein kinase(ERK1/2) pathway, ternary complex factor phospho-Elk-1, in rat brains with chronic fluorosis, and reveal the mechanism of the impaired learning and memory ability caused by chronic fluorosis. Methods Seventy-two SD rats, weighing 100 - 120 g, were randomly divided into 3 groups, 24 in each group (half male and half female). The rats in control group were fed with tap water (fluoride < 0.5 mg/L); low- and high-dose fluoride groups were fed with tap water with different concentrations of NaF(5.0,50.0 mg/L F-, respectively). After 6 months, body weight was weighed, dental fluorosis was determined by observation and urinary fluoride and bone fluoride were detected by fluorine ion-selective electrode; the learning ability of rats was measured by navigation test of Morris water maze, and memory ability by spatial probe test in Morris water maze; the expression and distribution of phospho-Elk-1 in different brain regions were detected by immunohistochemistry method. Results In low- and high-fluoride groups, the body weight of rat[(449.2 ± 77.1), (312.8 ± 89.7)g] was significantly decreased than that of control [(635.5 ± 76.2 )g, all P< 0.05], the varying degrees of dental fluorosis were observed(x2 = 7.83, P<0.05), urinary fluoride[(2.56 ±0.91),(5.73 ±3.14)mg/L] and bone fluoride[(709.2 ± 37.4) ,(1306.3 ± 102.4) mg/kg] were significantly higher than those in controls[(0.92 ± 0.30)mg/L,(348.5 ± 89.2)mg/kg, all P< 0.05]. The escape latency of low- and high-fluoride groups[ (7.4 ± 4.1), (12.2 ± 5.7)s] was longer than that of control [(4.8 ± 2.7 )s, all P < 0.05] and the escape latency in high-fluoride group was significantly longer than that in other groups (all P < 0.05); in spatial probe test, the time of first crossing platform was longer in rats with fluorosis [(4.18 ± 1.10),(5.89 ± 0.56)s] as compared to control[(1.17 ± 0.75)s, all P< 0.05]. Expressions of phospho-Elk-1 in the hippocampus CA1(167.4 ± 8.3,163.2 ± 9.4), CA2(175.7 ± 5.0,183.3 ± 4.2), CA3(165.2 ± 11.6,162.9 ± 4.4), CA4(168.7± 6.9,169.5 ±5.3), fascia dentate (185.2 ±4.0,193.1 ±6.1) and caudate putamen( 181.4 ± 3.8, 179.8 ± 5.5) in low- and high-fluoride groups were higher than those of controls(142.4 ± 8.1,144.9 ± 8.4,143.6 ± 5.8, 116.8 ± 9.1,140.2 ± 7.8,163.1 ± 13.1, all P< 0.05). Conclusion Chronic fluorosis can cause increased expression of phospho-Elk-1 in the hippocampus and caudate putamen region of rat brains, which might be related to the mechanisms of decreased learning and memory ability of rats overexposed to fluoride.     

氟对大鼠胆碱酯酶活性和学习记忆功能的影响

目的 研究氟对慢性氟中毒大鼠学习、记忆功能的影响以及其可能的机制,探讨氟对脑组织胆碱酯酶活性的影响多氟中毒大鼠智力损伤程度的关系.方法 SD大鼠按性别和体质量随机分为3组,对照组:自由饮用自来水,含氟量低于1mg/L;低剂量染氟组:饮水含氟量为5mg/L;高剂量染氟组:饮水含氟量为50mg/L.实验3个月时检测大鼠行为学变化和脑组织胆碱酯酶活性.结果 高剂量染氟组大鼠的逃避潜伏期时间[(17.55±1.51)s]长于对照组[(12.07±0.97)s],两组比较差异有统计学意义(P＜0.05);高剂量染氟组探索实验目标次数[(2.88±0.35)次]与对照组[(4.00±0.50)次]比较,有降低趋势,但差异无统计学意义(P＞0.05);高剂量染氟组的乙酰胆碱酯酶和丁酰胆碱酯酶活性[(1.41±0.19)、(0.49±0.07)kU/g]均低于对照组[(1.88±0.13)、(1.04±0.16)kU/g)],差异均有统计学意义(P＜0.05).结论 过量氟在体内蓄积可使大鼠智力降低,脑内的胆碱酯酶活性降低可能是其机制之一.     

氟铝联合对雄性大鼠性激素的影响

目的 了解氟铝联合对雄性大鼠性激素的影响.方法 选用断乳2周的健康SD雄性大鼠16只,按体质量随机分为4组,每组4只,分别为对照组及铝、氟、氟铝组.对照组和铝组喂饲的玉米饲料68%来自于非病区(含氟、铝各为5.2、6.8 mg/kg),分别给含铝0、90.0 mg/L的饮水;氟组、氟铝组给含68%的燃煤型氟中毒病区煤烘玉米饲料,含氟、铝量为106.0、19.7 mg/kg,并分别给予含铝0、90.0 mg/L的饮水.实验第90天后以出现明显氟斑牙为模型复制成功的判定指标.采集大鼠血样,用时间分辨免疫荧光法进行血清中睾酮(T)、雌二醇(E2)的测定.结果 大鼠血清T水平氟铝组[(15.994±6.558)μg/L]明显高于对照组[(3.317±0.635)μg/L],差异有统计学意义(P＜0.05),铝组[(8.134±3.134)μg/L]、氟组[(1.868±0.367)μg/L]、氟铝组[(12.687±2.979)μg/L]与对照组比较,差异无统计学意义(P＞0.05).大鼠血清E2氟组[(0.172±0.030)nmol/L]明显低于对照组[(0.319±0.072)nmol/L],差异有统计学意义(P＜0.05),铝组[(0.282±0.012)nmol/L]、氟铝组[(0.265±0.047)nmol/L]与对照组比较,差异无统计学意义(P＞0.05).氟和铝两因素存在交互作用(F=9.82,P＜0.05).结论 氟铝联合作用影响雄性大鼠性激素的水平.     

硒对高氟所致兔血管内皮损伤及动脉硬化影响的病理形态学研究

目的 研究硒对高氟所致兔动脉血管内皮细胞损伤和动脉硬化病理形态学变化的影响作用.方法 20只健康雄性新西兰白兔,体质量(2.0±0.5)kg,按体质量随机分对照组(饮去离子水,饲基础饲料)、加氟组(饮含氟离子100mg/L去离子水,饲基础饲料)、加硒组(饮含硒1 mg/L去离子水,饲基础饲料)、加氟加硒组(饮含氟离子100 mg/L、含硒1 mg/L去离子水,饲基础饲料),每组5只,实验期6个月.于实验第0、3、6个月取血测定血清含氟量和含硒量;实验终末取胸主动脉,观察主动脉病理及超微结构变化.结果实验第3、6个月时,加氟组和加氟加硒组血清氟[(0.589±0.146)、(0.772±0.175)mg/L和(0.502±0.094)、(0.693±0.158)mg/L]显著高于对照组[(0.174±0.002)、(0.208±0.031)mg/L,P均＜0.01];加氟组第6个月血清氟显著高于第3个月(P＜0.05).实验第3、6个月时,加硒组和加氟加硒组血清硒[(0.252±0.022)、(0.319±0.052)mg/L和(0.239±0.016)、(0.294±0.018)mg/L]显著高于对照组[(0.135±0.014)、(0.167±0.019)mg/L,P均＜0.01];加硒组第6个月血清硒显著高于第3个月(P＜0.05).对照组、加氟组、加硒组、加氟加硒组内皮细胞凋亡指数分别为(4.92±1.32)%、(30.30±6.80)%、(6.57±2.14)%和(14.29±2.99)%,氟与硒各自的主效应有统计学意义(F值分别为106.833、20.082,P均＜0.01),高氟与适硒之间存在显著的拮抗作用(F=30.402,P＜0.01).病理观察加氟组主动脉内皮有红细胞及纤维蛋白沉着,细胞走向及结构发生改变,血管受损严重;加氟加硒组减少内皮细胞凋亡,附着的纤维蛋白以及红细胞数量减少,内皮细胞结构基本正常,血管受损程度和范围明显减轻.结论适量硒抑制高氟引起的内皮细胞凋亡,减轻高氟所致主动脉结构破坏,保持内皮细胞的完整性,以此拮抗高氟对血管的损伤和促动脉粥样硬化作用.     

大豆、硒粉、螺旋藻对高摄铝下氟中毒大鼠的干预效果

目的 观察高摄铝状态下氟中毒大鼠大豆、硒粉、螺旋藻的干预效果.方法 将断乳2周的SD纯系大鼠40只(雌雄各半)按体质量随机分为5组:对照组、高氟铝组、高氟铝加大豆组、高氟铝加硒组和高氟铝加螺旋藻组,每组8只.对照组食用非病区玉米加工的饲料(含氟5.20 mg/L,含铝6.80 mg/L),饮用自来水(含氟0.70 mg/L,含铝0.20 mg/L).其余各组均食用以病区玉米为主加工而成的饲料(含氟110.00 mg/kg,含铝19.70mg/L),饮用自来水配制的高铝水(含氟0.70 mg/L,含铝90.00 mg/L).高氟铝加大豆组在实验开始即添加大豆(大豆占饲料的30%),高氟铝加硒组和高氟铝加螺旋藻组在动物出现氟斑牙后饲料中分别添加硒(3.00mg/kg)、螺旋藻(1000.00 mg/kg),实验期为22周.大鼠处死前收集24 h尿液,用于尿氟、铝的测定;大鼠处死后取四肢骨用于骨氟、铝测定;电镜下观察大鼠股骨松质骨的超微结构变化.结果 ①骨氟:高氟铝组的骨氟[(204.07±63.78)mg/kg]高于对照组、高氟铝加大豆组、高氟铝加硒组和高氟铝加螺旋藻组[(30.06±6.11)、(54.12±14.56)、(30.44±5.02)、(105.08±21.07)mg/kg,t=0.62、0.53、0.62、0.35,P均<0.01];高氟销加硒组骨氟低于高氟钒加螺旋藻组(t=0.27,P<0.01).②尿氟:高氟铝组尿氟[(4.52±3.09)mg/L]高于对照组[(0.89±0.37)mg/L,t=0.23,P<0.01],低于高氟铝加硒组[(10.38±1.58)mg/L,t=0.34,P<0.01];高氟铝加硒组尿氟高于高氟铝加大豆组、高氟铝加螺旋藻组[(5.56±1.69)、(4.38±3.36)mg/L,t=0.28、0.35,P均<0.01].③骨铝:对照组骨铝[(3.32±3.02)mg/kg]明显低于高氟铝组、高氟铝加大豆组、高氟铝加硒组和高氟铝加螺旋藻组[(374.21±56.11)、(118.20±23.59)、(114.01±22.84)、(67.11±11.53)mg/kg,t=1.42、0.44、0.42、0.24,P均<0.05];高氟销组骨铝也明显高于高氟铝加大豆组、高氟铝加硒组、高氟铝加螺旋藻组(t=0.56、0.57、0.68,P均<0.01);高氟铝加螺旋藻组骨铝低于高氟铝加大豆组、高氟铝加硒组(t=0.11、0.10,P均<0.05).④尿铝:高氟铝组尿铝[(1.14±0.32)mg/L]高于对照组、高氟铝加大豆组[(0.73±0.11)、(0.66±0.10)mg/L,t=1.92、2.24,P均<0.05].高氟铝加大豆组尿铝低于高氟铝加硒组、高氟铝加螺旋藻组[(1.03±0.22)、(1.10±0.28)mg/L,t=1.73、2.06,P均<0.05].⑤扫描电镜下高氟铝组骨胶原纤维排列紊乱,骨小梁发生融合成片,小梁吸收孔大多消失,其损害最为严重.在干预组其骨胶原纤维走向大致可见,小梁融合现象较高氟铝组为轻,其中以高氟铝加硒组改善为显著,高氟铝加螺旋藻组次之,而高氟铝加大豆组的作用稍弱.结论 饲料中加大豆、硒粉、螺旋藻对高摄铝状态下氟中毒大鼠的骨损伤具有缓解作用,其中以硒粉的作用最为显著.螺旋藻次之,而大豆的作用稍弱.     

八面蒙脱石联合莫沙必利灌胃对急性坏死性胰腺炎大鼠回肠NF-κB活化的影响

目的 探讨八面蒙脱石对急性坏死性胰腺炎(ANP)大鼠回肠黏膜NF-κB活化的影响.方法 120只雄性SD大鼠按完全随机法分为假手术组、ANP组、莫沙必利组、八面蒙脱石组和莫沙比利+八面蒙脱石(联合)组,每组24只大鼠.采用胰胆管内逆行注射牛磺胆酸钠诱导大鼠ANP模型;假手术组开腹注射生理盐水后关腹.各治疗组于造模前30 min分别给予相应药物灌胃1次.术后3、6、12 h分批处死动物.取胰腺组织行病理检查;取血测定TNF-a、IL-1水平;取回肠观察超微结构的改变;免疫组化法检测回肠黏膜NF-κB的表达;Western blotting法检测回肠组织IκBa水平.结果 与假手术组比较,ANP组胰腺损伤明显,血TNF-a、IL-1水平明显升高[(36.79±1.14)pg/ml对(9.00±0.01)pg/ml,(25.17±1.93)ng/ml对(3.45±0.11)ng/ml,P值均＜0.05],回肠绒毛高度显著下降[(0.25±0.22)×10~(-6)m对(1.50±0.33)×10~(-6)m,P＜0.05],柱状细胞指数显著降低[(2.40±1.65)×10~6个/m对(13.5±4.28)×10~6个/m,P＜0.05],NF-κB表达增加(6.92±1.54对1.28±0.29,P＜0.05),IκBa蛋白水平下降(3.30±1.99对24.32±1.93).莫沙必利组和八面蒙脱石组的各项指标与ANP组均无显著差异.联合组的血TNF-a、IL-1水平[(30.57±0.39)pg/ml和(13.45±1.26)ng/ml]、回肠绒毛高度和柱状细胞指数[(1.05±0.28)×10~(-6)m和(10.10±2.50)×10~6个/m]、NF-κB活化(4.32±1.57)和IκBa蛋白水平(15.99±1.26)均与ANP组有统计学差异(P值均＜0.05).结论 八面蒙脱石联合莫沙必利灌胃能减少ANP大鼠回肠黏膜NF-κB的大量激活,减轻胰腺和回肠黏膜的损伤程度.     

内毒素对肝星状细胞醛固酮分泌及核因子-κBP65 mRNA表达的影响

目的 探讨内毒素对大鼠肝星状细胞(HSC)醛固酮的分泌及核因子-κB P65(NF-κBP65)mRNA表达的影响.方法 传代培养大鼠HSC-T6,不同浓度内毒素处理细胞后分组.放射免疫法检测HSC分泌醛固酮的情况,半定量RT-PCR方法检测HSC表达NF-κB P65 mRNA的水平.应用方差分析、t检验和Pearson直线相关分析法进行统计学分析.结果 浓度为0.01、0.1、1.0和10.0 mg/L内毒素组醛固酮的分泌分别为(4.95±0.35)、(5.52±0.32)、(6.04±0.60)和(5.16±0.46)μg/L,显著高于对照组的(3.65±0.51)μg/L(t=2.9745,5.8725,6.8465,3.2065;均P＜0.05).浓度为0.01、0.1、1.0和10.0 mg/L内毒素组NF-κB P65 mRNA的表达分别为0.825±0.06、1.07±0.07、1.23±0.06和0.96±0.05,也明显高于对照组的0.43±0.04(t=5.4776,6.8084,7.9382,7.5136;均P＜0.01).10.0 mg/L内毒素组醛固酮的分泌和NF-κB P65 mRNA的表达均较1.0 mg/L内毒素组有明显降低(t=4.3865,3.7246;均P＜0.05).HSC中醛固酮的分泌与NF-κB P65 mRNA的表达存在正相关(r=0.886,P＜0.01).结论 一定浓度范围的内毒素可以上调大鼠HSC醛固酮的分泌和NF-κB P65 mRNA的表达,两者存在正相关和一定的剂量效应关系,这可能是引起肝纤维化的重要因素之一.     

蛋白激酶C/核因子κB信号通路在燃煤砷致人体T细胞活化中的作用

目的 了解燃煤砷暴露人群外周血T细胞活化情况及其外周血单个核细胞(PBMCs)内蛋白激酶C/核因子κB(PKC/NF-κB)途径相关信号分子的表达或活化情况,探讨PKC/NF-κB信号通路在燃煤砷致人体T细胞活化中的作用.方法 按照<地方性砷中毒诊断标准>(WS/T 211-2001)将贵州省兴仁县交乐村燃煤污染型地方性砷中毒病区94例居民分为无症状暴露组(12例)、轻度砷中毒组(33例)、中度砷中毒组(34例)及重度砷中毒组(15例);以距病区约12 km的非砷污染某村居民27例作为对照组.采用流式细胞术检测外周血活化T细胞比例;电泳迁移率改变实验(EMSA)检测PBMCs内NF-κB结合DNA的活性:蛋白印迹法检测PBMCs胞浆内PKCθ及磷酸化蛋白激酶Cθ(pPKCθ)表达水平.结果 外周血活化T细胞比例,各组间比较差异有统计学意义(F=7.893,P<0.01),无症状暴露组[(21.76±15.31)%]及轻、中、重度砷中毒组[(18.41±11.36)%、(17.78±11.93)%和(18.79±13.38)%]与对照组[(3.19±2.12)%]比较明显增加(P<0.05或<0.01);无症状暴露组及轻、中、重度砷中毒组PBMCs内NF-κB结合DNA的活性(1.49±0.24、1.58±0.30、1.57±0.34、1.51±0.16)与对照组(1.30±0.17)比较,差异有统计学意义(P<0.05或<0.01).PBMCs胞浆PKCθ表达水平.组间比较差异无统计学意义(F=1.843,P>0.05).pPKCθ表达水平,组间比较差异有统计学意义(F=6.588,P<0.01),轻、中、重度砷中毒组(0.64±0.14、0.64±0.20、0.62±0.12)与对照组(0.93±0.20)及无症状暴露组(0.81±0.23)比较,明显降低(P<0.05或<0.01).PBMCs内pPKCθ表达水平与NF-κB结合DNA的活性呈明显负相关(r=-0.565,P<0.01).NF-κB结合DNA的活性与外周血活化T细胞比例呈明显正相关(r=0.546,P<0.01).结论 燃煤砷暴露可显著增强人体PBMCs内PKCθ的活化及NF-κB结合DNA的活性,并诱导人体T细胞的活化,提示PKC/NF-κB信号通路可能是燃煤砷引起人体T细胞活化的信号途径之一.     

慢性氟中毒大鼠脑组织氧化应激水平及学习记忆功能的变化

目的 观察慢性氟中毒大鼠脑组织及血浆氧化应激水平的改变,探讨氟中毒性神经损害发病机制中氧化应激水平与学习记忆的关系.方法 SD大鼠按体质量随机分为3组,每组8只.对照组:自由饮用自来水,自来水含氟量低于0.5 mg/L;低剂量染氟组:饮水含氟量为5 mg/L;高剂量染氟组:饮水含氟量为50ms/L.实验期为6个月.检测大鼠学习记忆功能、血浆和脑组织总抗氧化能力(T-AOC)及丙二醛(MDA)水平.结果 高剂量染氟组大鼠逃避潜伏期[(14.37±3.48)s]长于对照组[(5.84±1.87)s]和低剂量染氟组[(7.18±1.42)s],两组间比较差异有统计学意义(P<0.05);高剂量染氟组、低剂量染氟组大鼠血浆和脑组织T-AOC水平[(1.37±0.27)×103 U/L、(0.24±0.06)×103 U/g Pr,(1.20±0.14)×103 U/L、(0.41±0.10)×103 U/g Pr]低于对照组[(2.17±0.11)×103 U/L,(0.79±0.11)×103 U/g Pr],两组间比较差异有统计学意义(P<0.05);高剂量染氟组大鼠血浆和脑组织MDA水平[(3.72±0.59)mmol/L、(4.01±0.21)mmol/g Pr]显著高于对照组[(2.34±0.16)nunol/L、(2.97±0.11)mmol/g Pr]和低剂量染氟组[(2.68±0.33)mmol/L、(3.38±0.21)mmol/g Pr],两组间比较差异有统计学意义(P<0.05).结论 慢性氟中毒可使机体氧化应激水平升高,大鼠学习记忆能力减退可能与氧化应激水平的升高有关.