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1.
本工作研究了慢性常压缺氧和缺氧件CO2潴留肺动脉高压大鼠红细胞变形能力和红细胞内ATP含量的变化。结果表明,慢性常压缺氧和缺氧伴CO2潴留大鼠不同切应力下的红细胞变形指数和红细胞内ATP含量均明显低于其对照组,且该两组红细胞内ATP含量与不同切应力下的红细胞变形指数呈显著正相关。提示慢性缺氧和伴CO2潴留大鼠红细胞内ATP含量降低可能是导致红细胞变形能力降低的诸因素之一,后者又可导致和加重肺动脉高  相似文献   

2.
缺氧时大鼠红细胞变形性损伤的机制研究   总被引:5,自引:0,他引:5  
本实验通过测定平原和模拟高原减压缺氧30天大鼠红细胞滤过指数(IF)、红细胞内[pH]i、[K+]i/[Na+]i比值、[Ca2+]i、[Mg2+]i、平均红细胞体积(MCV)及平均红细胞血红蛋白浓度(MCHC),从而探讨缺氧条件下大鼠红细胞变形性损害的机制。结果发现:1.缺氧组大鼠红细胞[Ca2+]i明显升高,且与IF呈显著正相关,但[Mg2+]i无明显差异;2.缺氧组[K+]i/[Na+]i值较平原组明显降低,且与IF呈显著负相关;3.缺氧组MCHC与平原组无明显差异,但MCV显著升高;4.缺氧组红细胞内[pH]i较平原组明显升高。提示:缺氧时红细胞[Ca2+]i升高,[K+]i/[Na+]i值降低,MCV增大以及红细胞[pH]i值的改变在其变形性损伤中起重要作用。  相似文献   

3.
实验性红细胞增多和慢性缺氧对右心室肥大的影响   总被引:1,自引:0,他引:1  
为了研究红细胞增多对缺氧性肺动脉高压和右室肥大的影响,将大鼠分为四组:常氧对照组;单纯红细胞增多组;慢性缺氧组;慢性缺氧复合红细胞增多组。结果表明,单纯红细胞增多引起右室V_(max)、右室收缩压和右室重量指数增加。慢性缺氧不仅引起右室±dP/dt_(max)和V_(max)增加,还引起右室收缩压和右室重量指数增加。慢性缺氧复合红细胞增多进一步使右室收缩压和右室重量指数增加。此外,还出现左室重量指数增加。以上结果表明,红细胞增多在缺氧性肺动脉高压和右室肥大中起着重要作用。  相似文献   

4.
观察了吸入0.004%的一氧化氮(NO)对急、慢性缺氧大鼠血流动力学、缺氧性肺血管收缩反应(HPV)、血气及高铁血红蛋白(MetHb)的影响。结果表明:(1)常氧吸入NO时能明显降低慢性缺氧大鼠肺动脉平均压(Ppa)和肺血管阻力(PVR),但对正常大鼠的Ppa和PVR无明显影响;(2)慢性缺氧大鼠急性缺氧时HPV较正常大鼠弱,吸入NO不但降低两者的急性缺氧肺动脉高压,且完全逆转两者的HPV;(3)吸入NO对急、慢性缺氧大鼠体循环血流动力学、血气及MetHb含量无明显影响。提示吸入NO能选择性降低急、慢性缺氧性肺动脉高压,且逆转HPV。  相似文献   

5.
Wang PY  Liu J  Yu ZH  Xu SM  Luo DC  Sun BY 《生理学报》1998,50(2):193-198
缺氧是否通过影响血管平滑肌细胞的自分泌功能而参与缺氧性肺动脉高压的发生尚不清楚。本实验动态了缺氧对培养的新生小牛肺动脉平滑肌细胞(PASMCs)的血管紧张素Ⅱ(ATⅡ)分泌的影响。结果发现:2.5%O2缺氧导致PASMCs的ATⅡ分泌降低,0%O2缺氧进一步抑制ATⅡ分泌。常氧条件下,NO供体SIN-1显著的抑制ATⅡ分泌,而NO合酶凶制剂硝基精氨酸(LNA)则能消除缺氧对ATⅡ分泌的抑制作用。0  相似文献   

6.
将大鼠置于模拟海拔8km高度的低压舱内缺氧1周及缺氧后空气中常氧恢复1周和2周,观察了左右心室功能、心肌肥厚、心肌收缩蛋白含量及其Ca ̄(2+),Mg ̄(2+)-ATP酶活性的动态变化。结果表明,8km缺氧1周后肺动脉压及右心室收缩压明显升高,左右心室±dp/dtmax及收缩指数明显降低。左右心室肌明显肥厚,心肌收缩蛋白Ca ̄(2+),Mg ̄(2+)-ATP酶活性明显减低。缺氧后常氧恢复1和2周后,左右心室功能逐渐恢复达到或接近正常水平,心肌肥厚逐渐减轻或恢复正常,心肌收缩蛋白Ca ̄(2+),Mg ̄(2+)-ATP酶活性也逐渐升高。因此说明:心肌收缩蛋白Ca ̄(2+),Mg ̄(2+)-ATP酶活性的改变是心功能变化的重要生化基础之一,它的减低是缺氧心肌对环境的代偿适应。  相似文献   

7.
应用分子杂交技术和放射免疫检测方法研究了缺氧对猪肺动脉内皮细胞的环氧合酶(COX)和血栓素合成酶(TXS)基因表达及其条件培养基中6ketoPGF1α和TXB2含量的动态变化。发现:6,12,24和48h缺氧组分别与常氧组比,COX1和COX2基因表达增加,并且COX2mRNA在缺氧6和12h就明显表达增加。在前述的不同缺氧时间组内皮细胞条件培养基中6ketoPGF1α含量也均显著高于相应常氧对照组(P<0.05);但TXS的mRNA水平及TXB2含量在缺氧48h才有明显增加(P<0.05)。结果表明:(1)缺氧可诱导肺动脉内皮COX基因表达和PGI2生成增加,在早期以COX2基因表达增加更为明显,提示可能在肺血管缺氧反应中起调节作用。(2)48h的缺氧可使内皮细胞TXS基因表达及TXA2生成增加,它可能在慢性缺氧肺血管反应中起介导作用。  相似文献   

8.
慢性缺氧对大鼠肺内皮素表达的影响   总被引:2,自引:0,他引:2  
本文以ABC法和原位杂交技术,观察了慢性缺氧时大鼠肺组织内内皮素-1(ET-1)的表达情况,结果发现:①正常肺血管内皮细胞有少许ET-1样阳性染色物质呈现。②缺氧IW后,肺内ET-1含量增加,主要位于肺血管内皮细胞和支气管粘膜上皮细胞。③缺氧2W和3W后,ET1阳性免疫物质进一步增加,于肺泡细胞内也见到阳性染色。④缺氧1W后肺内ET-1mRNA表达增加,缺氧2W和3W后,ET-1mRNA的表达进一步加强。提示缺氧可刺激肺内ET-1mRNA的表达,慢性缺氧时肺内ET-1持续分泌增加,这可能是缺氧性肺动脉高压发生的重要因素之一。  相似文献   

9.
缺氧对培养的肺动脉内皮细胞血管紧张素Ⅱ分泌的影响   总被引:2,自引:0,他引:2  
缺氧是否通过影响血管内皮细胞的分泌功能而参与缺氧性肺动脉高压的发生尚不清楚。本实验动态观察了缺氧对培养的新生小牛内皮细胞(PAEC)的血管紧张素Ⅱ(ATⅡ)分泌的影响。结果发现:2.5%O2缺氧早期(1.5h),PAEC的ATⅡ分泌增加(P<0.01vs常氧组),缺氧后期与常氧组无明显差别;0%O2缺氧早期(1.5-6h),ATⅡ分泌明显降低(P<0.01vs常氧组及2.5%O2组),后期ATⅡ分泌明显增高(P<0.01vs常氧组及2.5%O2组);无论缺氧还是常氧条件下,NO供体SIN1显著抑制ATⅡ的分泌(P<0.01),而内源性NO抑制剂硝基精氨酸则明显促进ATⅡ分泌(P<0.01);0%O2缺氧24h后,PAEC细胞内cGMP含量明显降低(P<0.05)。上述结果表明缺氧可通过抑制PAEC的内源性NO产生而促进ATⅡ的分泌,PAEC自分泌的改变可能参与缺氧性肺动脉高压的发生过程。  相似文献   

10.
茶多酚对大鼠慢性缺氧损伤保护的实验研究   总被引:4,自引:0,他引:4  
大鼠在高原环境模拟舱内间断缺氧及注射CoCl2溶液以建立红细胞增多症模型,实验分4组:平原组、慢性缺氧组、高剂量TP+慢性缺氧组、低剂量TP+慢性缺氧组,研究茶多酚对慢性缺氧诱导的大鼠红细胞增多症及心肌缺氧损伤的影响.结果显示,茶多酚能够显著抑制缺氧大鼠的红细胞数、血红蛋白和红细胞压积的增加,降低骨髓增生程度,减小缺氧大鼠心室重量指数,增加缺氧大鼠Hermannnwillson指数,同时经茶多酚处萼的缺氧大鼠心肌损伤程度较单纯缺氧组轻.提示,茶多酚对大鼠红细胞增多症有一定的预防作用,同时茶多酚还能减轻慢性缺氧对大鼠的心肌损伤程度.  相似文献   

11.
目的:探讨高原低氧习服大鼠红细胞变形性的变化规律及其分子机制。方法:将健康雄性大鼠随机分为3组(n=10):常氧对照组、急性低氧组和低氧习服组。模拟高原低氧环境对大鼠分别进行急性低氧和间断低氧习服,麻醉后心脏采血,分别测定大鼠红细胞变形性、膜流动性、膜胆固醇和总磷脂含量、膜磷脂成分的含量、红细胞ATP酶活性、红细胞内Na+和Ca2+浓度及建立红细胞膜蛋白质双向电泳图谱,寻找差异蛋白质点,对其进行质谱鉴定。结果:①急性低氧大鼠红细胞变形性、膜流动性、膜胆固醇和总磷脂含量、红细胞ATP酶活性均降低;红细胞内Na+和Ca2+浓度均增高;红细胞膜磷脂酰丝氨酸(PS)、鞘磷脂(SM)含量增加,磷脂酰胆碱(PC)含量降低;建立了红细胞膜蛋白质双向电泳图谱,选取7个差异蛋白质点,其中4个在急性低氧后表达降低。②低氧习服大鼠红细胞变形性、膜流动性、膜胆固醇和总磷脂含量、红细胞ATP酶活性明显均增高;红细胞内Na+和Ca2+浓度均降低;红细胞膜PS、SM含量降低,PC含量增加;上述7个差异蛋白质点中4个在低氧习服后表达增高,3个表达降低,质谱技术鉴定结果为补体结合蛋白、水通道蛋白、膜攻击复合物抑制因子、葡萄糖运载体、脂质移行酶、氨基磷脂转移酶、依赖ATP的翻转酶,其中后三个酶与红细胞膜磷脂翻转有关。结论:急性低氧引起红细胞变形性、膜流动性、膜蛋白质表达、红细胞ATP酶活性及胞内Na+和Ca2+浓度方面相应的改变;经低氧习服后,上述指标有所改善,低氧习服对急性低氧引起红细胞的影响具有一定的保护作用;红细胞膜上的3种蛋白质,包括脂质移行酶、氨基磷脂转移酶和依赖ATP的翻转酶在低氧习服改善红细胞变形性的机制中可能发挥重要的作用。  相似文献   

12.
目的:探讨红细胞膜蛋白在红细胞变形性改变中的作用。方法:参照Leammli和Peacock方法,测定了肺心病Ⅰ型呼吸衰竭(Ⅰ组)18例、Ⅱ型呼吸衰竭(Ⅱ组)18例和健康对照(CG)20例的红细胞膜带3蛋白、膜收缩蛋白二聚体(SpD)和四聚体(SpT)的相对含量与红细胞变形能力。结果:Ⅰ、Ⅱ组带3蛋白、SpD、SpT相对含量和红细胞变形指数(DI)与对照组均有显著差异,且肺心病病人的DI与带3蛋白相对含量呈显著正相关,与SpD/SpT比值呈显著负相关。结论:带3蛋白和膜收缩蛋白的异常,可能是导致肺心病人红细胞变形能力降低的重要因素之一。  相似文献   

13.
目的 :探讨运动对红细胞变形性和红细胞膜蛋白的影响及其相互关系。方法 :设计不同强度的训练方案 ,用激光衍射法测定红细胞变形能力 ,用SDS PAGE方法测定一定体积大鼠红细胞膜中的重要蛋白带 3蛋白 (band 3)和肌动蛋白 (actin)的含量 ,研究运动即刻和恢复后红细胞变形性及膜蛋白的变化。结果 :长期的运动训练会促进大鼠红细胞变形能力的改善和红细胞膜band 3蛋白和actin的良好发展 ,一次大强度训练会引起红细胞膜band 3蛋白和actin含量的减少 ,大鼠红细胞变形能力降低 ,一周和二周的大强度训练会提高恢复期大鼠红细胞的变形能力和红细胞膜band 3蛋白和actin含量。结论 :运动训练造成的红细胞膜蛋白含量的变化 ,导致了红细胞膜结构的改变 ,从而影响红细胞变形能力 ,可能是训练对红细胞变形能力的作用机制之一。  相似文献   

14.
肠系膜淋巴管结扎对急性失血大鼠红细胞流变性的影响   总被引:1,自引:0,他引:1  
目的:观察结扎肠系膜淋巴管(MLD)对急性失血大鼠红细胞流变性的影响。方法:20只Wistar雄性大鼠随机均分为失血组与结扎组。所有大鼠经右侧颈总动脉匀速放血(失血量为全血量的1/4),结扎组失血后结扎MLD,失血组仅在MLD下穿线。记录24h存活情况。24h后,将存活大鼠经左侧颈总动脉迅速放血,测定实验前后的红细胞沉降率(ESR)、红细胞电泳、红细胞压积(Hct),计算红细胞聚集与变形指数。结果:急性失血后24h,结扎组大鼠存活情况(9只)略好于失血组(6只)。急性失血后24h,与实验前相比,失血组与结扎组的ESR、血沉方程K值、校正K值、红细胞电泳时间均显著升高或延长,红细胞变形性降低,失血组的红细胞聚集指数显著升高、红细胞电泳长度与迁移率均显著降低;结扎组的ESR、血沉方程K值、校正K值、红细胞聚集指数、电泳时间较失血组显著降低,红细胞电泳长度与迁移率、变形性较失血组显著升高。结论:急性失血导致大鼠红细胞聚集性升高、红细胞电泳能力及变形性降低,结扎MLD可改善急性失血导致的红细胞流变性异常。  相似文献   

15.
目的:观察肠淋巴液引流对失血性休克大鼠红细胞流变性指标以及血液黏度的作用。方法:Wistar雄性大鼠均分为假休克组、休克组(复制失血性休克模型)、引流组(复制失血性休克模型,自低血压1 h引流休克肠淋巴液)。在低血压3 h或相应时间,经腹主动脉取血,检测红细胞参数、红细胞电泳、红细胞沉降率(ESR)以及血液黏度,计算红细胞聚集指数、红细胞变形指数。结果:与假休克组比较,休克组红细胞数量、红细胞比积(HCT)、血红蛋白(Hb)、平均红细胞血红蛋白浓度(MCHC)、红细胞电泳率与迁移率、红细胞变形指数、全血黏度、全血低切与高切相对黏度和还原黏度显著降低,休克组平均红细胞体积、红细胞电泳时间、ESR、血沉方程K值与校正K值、红细胞聚集性指数、血浆黏度显著升高;引流组MCHC、红细胞电泳率与迁移率、全血黏度、全血低切与高切还原黏度均显著降低,引流组红细胞体积分布宽度(RDW-SD)显著增加。同时,引流组HCT、RDW-SD、红细胞变形指数、全血黏度、全血低切与高切相对黏度显著高于休克组;ESR、血沉方程K值与校正K值、红细胞聚集性指数、血浆黏度显著低于休克组。结论:休克肠淋巴液引流可改善失血性休克大鼠红细胞流变行为,从而改善血液流变性。  相似文献   

16.
T S Hakim  A S Macek 《Biorheology》1988,25(6):857-868
The contribution of erythrocyte deformability to the pulmonary vascular resistance during hypoxia in different animal species has not been examined. We hypothesized that the increase in pulmonary vascular resistance during hypoxia was partially due to erythrocytes (RBC's) becoming less deformable during hypoxia, and therefore their transit in the capillaries becomes restricted. To test this, we measured an index of deformability of RBC's from six animal species (dog, pig, cat, rabbit, hamster, rat) during normoxic and hypoxic condition, and compared the changes in deformability with the pulmonary hypoxic pressor response (HPR) which has been reported in the same species. Deformability was indexed as the resistance that a Hemafil polycarbonate membrane (Nucleopore filter, 4.7 micron pores) offers to a 10% suspension of RBC's. The RBC suspension was either normoxic (PO2 = 150 torr) or hypoxic (PO2 = 50 torr). We found that hypoxia decreased RBC deformability; the largest decrease occurred in rat RBC's, a small but significant decrease was observed in the RBC's of cats, rabbits and hamsters, but no change was detected in RBC's of dogs or pigs. In general, such changes in deformability do not correlate well with the HPR in intact or in isolated lungs, for example the pig, had the largest HPR but the smallest change in RBC deformability. In some species, however, there was a positive correlation between RBC deformability and HPR, for example rats, rabbits and cats are usually better responders than dogs and hamsters, similarly the deformability of RBC's in rats, rabbits and cats were also more influenced by hypoxia than RBC's from dogs. The limiting factors in this relationship are the artificial conditions which were used to measure deformability and HPR, both may be different than in the intact conditions. Nevertheless the present data show that erythrocytes of some species can become less flexible during hypoxia, and hence may impede the transit in the capillaries. Therefore we propose that the hypoxic pressor response in the pulmonary vasculature may be partly due to smooth muscle contraction (vasoconstriction) and partly due to a decrease in erythrocyte deformability (capillary obstruction). Both components are likely to be species dependent.  相似文献   

17.
To evaluate chronic ethanol toxicity on erythrocyte membrane and preventive action of betaine as a methyl donor, 24 male Wistar albino rats were divided into three groups: control, ethanol and ethanol plus betaine group. Animals were fed 60 ml diet per day for two months. Rats in the ethanol group were fed ethanol 8 g/kg/day. The ethanol + betaine groups were fed ethanol plus betaine (0.5% w/v). After two months, all animals were killed. Malondialdehyde (MDA) and sialic acid (SA) levels were determined in plasma samples. Osmotic fragility tests were performed on whole blood samples and erythrocyte membrane thiol contents were determined using membrane suspensions. Plasma MDA levels in ethanol-given rats were increased significantly compared to the control group of rats (p < 0.05). MDA in the betaine group was significantly lower than that in the ethanol group (p < 0.05). Erythrocyte membrane thiol contents in ethanol group were decreased compared with those of the control group (p < 0.05). Thiol contents were increased slightly after betaine therapy, but this increase was not statistically significant (p > 0.05). Plasma sialic acid levels in the ethanol group were significantly higher than in the control group (p < 0.05). Sialic acid was decreased in the betaine group compared to the ethanol group (p < 0.05). In the osmotic fragility test, we observed that chronic ethanol consumption increased erythrocyte hemolysis. Betaine protected against ethanol-induced hemolysis. Our findings show that chronic ethanol administration affects erythrocyte membrane properties and this may be related to oxidative stress. Betaine protects erythrocyte membrane alterations against chronic ethanol toxicity. Therefore betaine as a nutritional agent, may protect ethanol induced clinical problems associated with membrane abnormalities.  相似文献   

18.
Low oxygen (O(2)) tension and mechanical deformation are stimuli for ATP release from erythrocytes. It has been shown previously that rabbit erythrocytes made less deformable with diamide, a thiol cross-linking agent, release less ATP in response to low O(2) tension, suggesting a link between these two stimuli. In nonerythroid cells, activation of the Rho/Rho kinase signaling pathway has been reported to decrease cell deformability by altering Rho kinase-dependent cytoskeleton-protein interactions. We investigated the hypothesis that the Rho kinase inhibitor Y-27632 would increase erythrocyte deformability and thereby increase low O(2) tension-induced ATP release from erythrocytes. Here we show that Y-27632 (1 μM) increases erythrocyte deformability (5%) and increases low O(2) tension-induced ATP release (203%) from healthy human erythrocytes. In addition, we found that, when erythrocytes were made less deformable by incubation with diamide (100 μM), Y-27632 restored both deformability and low O(2) tension-induced ATP release to levels similar to those measured in the absence of diamide. These findings suggest that the Rho kinase inhibitor Y-27632 is able to reverse the diamide-induced decrease in erythrocyte deformability and rescue low O(2) tension-induced ATP release. These results further support a link between erythrocyte deformability and ATP release in response to low O(2) tension.  相似文献   

19.
Despite enhancing cardiopulmonary and muscular fitness, the effect of hypoxic exercise training (HE) on hemorheological regulation remains unclear. This study investigates how HE modulates erythrocyte rheological properties and further explores the underlying mechanisms in the hemorheological alterations. Twenty-four sedentary males were randomly divided into hypoxic (HE; n = 12) and normoxic (NE; n = 12) exercise training groups. The subjects were trained on 60% of maximum work rate under 15% (HE) or 21% (NE) O(2) condition for 30 min daily, 5 days weekly for 5 wk. The results demonstrated that HE 1) downregulated CD47 and CD147 expressions on erythrocytes, 2) decreased actin and spectrin contents in erythrocytes, 3) reduced erythrocyte deformability under shear flow, and 4) diminished erythrocyte volume changed by hypotonic stress. Treatment of erythrocytes with H(2)O(2) that mimicked in vivo prooxidative status resulted in the cell shrinkage, rigidity, and phosphatidylserine exposure, whereas HE enhanced the eryptotic responses to H(2)O(2). However, HE decreased the degrees of clotrimazole to blunt ionomycin-induced shrinkage, rigidity, and cytoskeleton breakdown of erythrocytes, referred to as Gardos effects. Reduced erythrocyte deformability by H(2)O(2) was inversely related to the erythrocyte Gardos effect on the rheological function. Conversely, NE intervention did not significantly change resting and exercise erythrocyte rheological properties. Therefore, we conclude that HE rather than NE reduces erythrocyte deformability and volume regulation, accompanied by an increase in the eryptotic response to oxidative stress. Simultaneously, this intervention depresses Gardos channel-modulated erythrocyte rheological functions. Results of this study provide further insight into erythrocyte senescence induced by HE.  相似文献   

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