盐胁迫下外源水杨酸对菊花根系离子含量和ATPase及PPase活性的影响

 采用水杨酸（SA）叶面喷施法，研究了NaCl胁迫下外源SA对菊花根系Na+、K+、Ca2+ 、Mg2+含量以及根系质膜ATPase、液泡膜ATPase和PPase活性的影响。结果表明，盐胁迫增加了菊花根系中Na+的含量而减少了K+、Ca2+、Mg2+的含量，而外源SA处理减少了Na+的含量并增加了K+、Ca2+、Mg2+的含量。NaCl胁迫下菊花根系质膜ATPase、液泡膜ATPase和PPase活性均明显下降，外源SA处理减小了盐胁迫引起的质膜ATPase、液泡膜ATPase和PPase活性的下降幅度，而且在胁迫10 d时，外源SA处理的根系质膜ATPase、液泡膜ATPase和PPase活性分别比NaCl处理提高了17.67%、16.47%和18.65%。说明盐胁迫下外源SA可以通过诱导质子泵活性来提高菊花根系对K+、Ca2+ 、Mg2+的吸收和减少对Na+的吸收，从而缓解盐胁迫对菊花植株的伤害程度。     

外源钙对根际低氧胁迫下黄瓜植株钾、钙、镁离子含量和ATPase活性的影响

以黄瓜(Cucumis sativus L.)'新泰密刺'品种为材料,采用营养液栽培,研究了外源Ca2+对根际低氧胁迫下幼苗植株离子含量和ATPase活性的影响。结果表明,常钙低氧处理植株体内K+、Ca2+、Mg2+含量和质膜、液泡膜、内质网膜ATPase活性显著降低;营养液增施4mmol·L-1CaCl2明显缓解了低氧胁迫对植株的伤害,根中K+、Ca2+、Mg2+含量,根系质膜、液泡膜、内质网膜H+-ATPase和Ca2+-ATPase活性,显著高于常钙低氧处理,接近或达到对照水平;根际低氧胁迫下营养液增施Ca2+通道抑制剂La3+(50μmol·L-1H+)显著,降低了幼苗体内K+、Ca2+含量,但对Mg2+含量影响不显著,营养液增施La3+显著降低了质膜H+-ATPase和Ca2+-ATPase的活性,但对液泡膜,内质网膜H+-ATPase和Ca2+-ATPase活性影响不显著。外源钙通过增加黄瓜体内矿质营养离子的吸收和转运,维持质膜、液泡膜和内质网膜ATPase活性,从而缓解低氧胁迫对植株造成的伤害,增强黄瓜植株的低氧耐性。     

Effects of volatile anesthetics on rat heart ischemia-reperfusion injury in vitro

AIM: To investigate the effect of volatile anesthetics on function,metabolism,ATPase activity and free radicals in isolated ischemia /reperfusion (I/R) rat hearts.METHODS: 136 SD rats were anesthetized with pentobarbital and randomly divided into six groups and 17 sub-groups (n=8),according to the given drug.In a normal thermal isolated Langendorff rat heart model,four volatile anesthetics in 1.5 MAC concentration were given before global ischemia 25 min and during reperfusion 30 min.Coronary flow (CF),LVEDP,left ventricular developed pressure (LVDP),±dp/dt were monitored at 15 min of equilibrium,15 min of drug treatment,the end of reperfusion.Myocardial adenosine triphosphate (ATP),malodialdehyde (MDA),activity of Ca2＋-ATPase and Na＋-K＋-ATPase,and superoxide dismutase (SOD) were determined at 15 min of equilibrium,15 min of drug treatment or absence,10 min global ischemia and the end of reperfusion.RESULTS: CF and LVEDP were increased significantly after exposured to volatile anesthetics 15 min,and LVDP,+dp/dtmax were significantly decreased.However,LVDP and +dp/dtmax were increased at the end of reperfusion in the treated groups.HR in halothane and isoflurane groups was decreased before ischemia and after reperfusion.The myocardial ATP content was significantly increased before and after ischemia in the treated groups.At the end of reperfusion,the activity of SOD was significantly higher and myocardial MDA content was significantly lower in the treated groups than those in control group.The activity of Ca2＋-ATPase,compared with the control group,was markedly decreased before ischemia in halothane,enflurane and isoflurane group.Nonetheless,the activity of Ca2＋-ATPase was clearly increased in the treated groups during ischemia and at the end of reperfusion.The activity of Na＋-K＋-ATPase was only enhanced in halothane group at the end of reperfusion among groups.CONCLUSION: The volatile anesthetics depress myocardial systolic function.There are markedly protective effects against myocardial I/R injury.Meanwhile,the volatile anesthetics improve the recovery of function and metabolism,and increase CF and the activity of Ca2＋-ATPase and Na＋-K＋-ATPase in rats.     

Mesenteric lymph reperfusion exacerbates brain injury in superior mesenteric artery occlusion shock rats

AIM: To observe the effect of mesenteric lymph reperfusion (MLR) on the brain morphology and neurotransmitter in rats with superior mesenteric artery occlusion (SMAO) shock, and to explore the mechanism of oxygen free radicals, nitric oxide (NO), polymorphonuclear neutrophils (PMN), membrane ATPase function and energy metabolism. METHODS: Twenty-four male Wistar rats were randomly divided into 4 groups: in sham group, the rats were given only anesthetization and operation; in MLR group, the rats were performed 1 h occlusion of mesenteric lymphatics (ML) followed by 2 h of reperfusion; in SMAO group, the rats were performed 1 h occlusion of superior mesenteric artery (SMA) followed by 2 h of reperfusion; in MLR+SMAO group, the rats were performed 1 h occlusion of SMA and ML followed by 2 h of reperfusion. After 2 h of reperfusion, the brain tissue was taken for preparing microscopic sections to observe the morphological change. At the same time, the brain tissue was homogenized for determining the choline acetyltransferase (ChAT), acetylcholine esterase (AChE), dopamine (DA), norepinephrine (NE), lactic acid (LA), malondialdehyde (MDA), superoxide dismutase (SOD), NO, nitric oxide synthase (NOS), myeloperoxidase (MPO), cell membrane ATPase and ATP. RESULTS: Morphological observation showed that the architecture of the brain was close to normal in sham and MLR groups. Necrosis, degeneration and occasional swelling were found in neuronal cells in SMAO group, and in MLR + SMAO group the injury of the neurons was more serious than that in SMAO group. The contents of MDA, NO and LA, the activities of AChE, NOS and MPO in brain homogenate in SMAO and MLR+SMAO groups were increased, the ChAT activity and DA, NE contents were reduced significantly than those in MLR and sham groups, respectively. The contents of MDA and NO, the activities of AChE, NOS and MPO in MLR+SMAO group were higher than those in SMAO group. The activities of Na+-K+-ATPase and SOD in brain homogenate in SMAO group were lower than those in sham and MLR groups, the Mg2+-ATPase activity and ATP content were lower than those in MLR group. The activities of SOD, Na+-K+-ATPase, Ca2+-ATPase, Mg2+-ATPase and Ca2+-Mg2+-ATPase in brain homogenate in MLR+SMAO group were lower than those in sham and MLR groups, and the DA, Ca2+-ATPase, Mg2+-ATPase, Ca2+-Mg2+-ATPase and ATP were also lower than those in SMAO group. CONCLUSION: MLR exacerbates the brain injury, reduces the DA level and increases the AChE activity in SMAO shock rats, indicating that MLR enhances the brain tissue free radical injury, NO synthesis and releases, PMN detention, and decreases the activity of cell membrane ATPase, also induces the energy metabolism dysfunction.     

香菇中γ-谷氨酰转肽酶的分离纯化及其酶学性质研究

通过(NH4)2SO4沉淀、Phenyl Sepharose FF疏水层析分离纯化香菇中的γ-谷氨酰转肽酶(γ-Glutamyltranspeptidase,GGT),纯化后的GGT的比活力到达了19.59 U/mg.SDS-PAGE分析表明,GGT由分子量分别为28 kDa和60 kDa的两个亚基组成.酶学性质试验结果表明,GGT反应的最适温度为37 ℃,最适pH 值为7.6;金属离子Na+、K+和Ca2+对酶有激活作用,而Ag+、Cu2+、Zn2+和Fe3+则有抑制作用;试验范围内,GGT水解γ-glutamyl-p-nitroanilide的米氏动力学参数Km 值为2.601 μmol/mL,Vmax值为0.0287 μmol/min;组成的氨基酸中,Glu和Asp含量较高,Met和Cys含量较低.     

The renal L-arginine/nitric oxide pathway and erythrocyte L-arginine transport in spontaneously hypertensive rats

AIM: To investigate the changes of the renal L-arginine /nitric oxide pathway and the relationship of L-arginine transport between kidney and erythrocytes in spontaneously hypertensive rat (SHR). METHODS: Sixteen week old SHR, 16 week old SHR with captopril (CAP) treated for four weeks and 16 week old WKY rats were used in the experiment. L-arginine transport, NO synthase(NOS) activity, nitrite and cyclic GMP (cGMP) content were measured in renal tissue or erythrocytes. RESULTS: In the renal tissue, compared with that of WKY group, the Vmax of high-or low-affinity L-arginine transporter, NOS activity, NO₂^- and cGMP content of SHR group were significantly decreased (P＜0.01 or P＜0.05). The Vmax of high-affinity L-arginine transporter and NOS activity of CAP group were significantly enhanced as compared with SHR group (+90%, P＜0.01; +58.6%, P＜0.05). The NOS activity had significant positive correlation with the Vmax of high-affinity L-arginine transporter (r=0.585, P＜0.05). The changes of erythrocyte L-arginine transport were the same as that of kidney. The Vmax of SHR group was lower than that of WKY group (-30%, P＜0.01), and the Vmax of CAP group was higher than that of SHR group (+26.5%, P＜0.01). Km was not significantly changed. There is a positive correlation between the Vmax of L-arginine transport in erythrocyte and the Vmax of high- or low-affinity L-arginine transporter in renal tissue, (r=0.8434, P＜0.01, high-affinity; r=0.5255, P＜0.05, low-affinity). CONCLUSION: There existed a functional inhibition in L-arginine/nitric oxide pathway in the kidney of SHR. It can be recovered obviously by captopril treatment. The changes of L-arginine transport in kidney coincide with that in erythrocyte.     

外源ABA对NaCl胁迫下黄瓜幼苗不同离子含量的影响

研究了外源ABA对NaCl胁迫下黄瓜幼苗不同器官中Na+、Cl-、K+和Ca2+含量的影响。结果表明,NaCl胁迫下,黄瓜幼苗体内Na+、Cl-含量升高;叶片中K+、Ca2+含量下降,Na+/K+、Na+/Ca2+增大,SK、Na、SCa、Na降低。外源ABA减少了叶片、根中Na+、Cl-的积累,抑制了叶片K+、Ca2+含量的降低,提高了K+、Ca2+的吸收和运输选择性。外源ABA可通过调控盐胁迫下植株体内的离子平衡,提高黄瓜幼苗的耐盐性。     

柑橘全爪螨Na+-K+-ATPase的生化毒理学特性研究

为明确柑橘全爪螨Na+-K+-ATPase与其抗药性之间的关系,采用微量滴度酶标板法对柑橘全爪螨敏感品系(SS)、甲氰菊酯抗性品系(FeR)和阿维菌素抗性品系(AvR)的Na+-K+-ATPase的生化毒理学特性进行了比较研究.结果表明,柑橘全爪螨Na+-K+-ATPase比活力从高到低依次为AvR、SS和FeR;柑橘...     

Effects of short-chain acyl-CoA dehydrogenase on hypertensive vascular remodeling

AIM: To investigate the changes of short-chain acyl-CoA dehydrogenase (SCAD) in hypertensive vascular remodeling and to explore the relationship between SCAD and vascular remodeling in hypertension.METHODS: The spontaneously hypertensive rats (SHR; 24 weeks old) and Wistar rats (24 weeks old) were used as experimental control groups. The SHR and Wistar rats of 16 weeks old were trained by swimming as experimental groups. The systolic pressure was measured periodically. The thickness of vascular wall and the diameter of the vascular lumen were measured. The contents of ROS and ATP, the enzyme activity of SCAD, and the expression of SCAD at mRNA and protein levels in the aorta were determined. The free fatty acid in the serum and aorta was also measured.RESULTS: Compared with Wistar group, the diameter of vascular lumen decreased in SHR group. The thickness of vascular wall, the ratio of vascular wall and the diameter of vascular lumen, and the blood pressure in SHR group were increased significantly (P<0.05). Compared with SHR group, the diameter of vascular lumen increased in SHR+swim group. The thickness of vascular wall, the ratio of vascular wall and the diameter of vascular lumen, and the blood pressure in SHR+swim group were decreased significantly. Compared with control group, the expression of SCAD at mRNA and protein levels, the enzyme activity of SCAD, and the content of ATP were decreased in SHR group. However, the free fatty acid in the serum and aorta, and the content of ROS in the aorta were increased in SHR group. The expression of SCAD at mRNA and protein levels, the enzyme activity of SCAD, the content of ATP were increased in Wistar+swim group and SHR+swim group. However, the free fatty acid in serum and aorta, and the content of ROS in the aorta were decreased in Wistar+swim group and SHR+swim group.CONCLUSION: Decrease in SCAD expression may be associated with hypertensive vascular remodeling. Swimming training can reverse hypertensive vascular remodeling by increasing the expression of SCAD in the aorta.     

草莓果实成熟过程中Ca~(2+)-ATPase活性变化及酶学特性

以不同成熟度的草莓果实为试材,研究了草莓果实成熟过程中Ca2+-ATPase活性变化规律、最适pH值、动力学参数Km值和Vmax值。研究结果表明,草莓果实从开始成熟时(绿熟期)Ca2+-ATPase活性不断升高,果实完全成熟时(粉红期)达到最大值,随着成熟后的不断衰老,其活性逐渐降低;该酶的最适pH值为7.0;不同成熟阶段果实Ca2+-ATPase反应所需的Ca2+浓度有所不同,EGTA对各成熟阶段草莓果实的Ca2+-ATPase活性的抑制作用存在明显的差异。经对Ca2+-ATPase的动力学分析表明,不同成熟度果实Ca2+-ATPase的Km值和Vmax值不同,从果实开始成熟Km值逐渐降低,衰老时又逐渐上升,变化趋势与酶活性变化趋势相反;Vmax值变化趋势与酶活性变化趋势相同。2+     

Endoxin antagonist up-regulates gene expression of sodium pump isoforms in rats with myocardial ischemia reperfusion injury

AIM: To observe the effect of endoxin antagonist,anti-digoxin antiserum,on endoxin level,ATPase activities,intramitochondrial total calcium concentration and gene expression of sodium pump isoforms in myocardium of rats with myocardial ischemia reperfusion (MIR).METHODS: Fifty-six male Sprauge Dawley rats were randomly divided into 7 groups.Sham operation group: silk suture threading the left anterior descending coronary artery without ligature;MIR group: left anterior descending coronary artery was subjected to 30 min ligation followed by 45 min reperfusion;normal saline group: MIR model was given 5 mL/kg normal saline;verapamil group: MIR model was given 5 mg/kg verapamil;low dose antidigoxin antiserum group: MIR model was given 8.6 mg/kg antidigoxin antiserum;middle dose antidigoxin antiserum group: MIR model was given 17.3 mg/kg antidigoxin antiserum;high dose antidigoxin antiserum group: MIR model was given 34.5 mg/kg antidigoxin antiserum.All drugs were injected into vessel via femoral vein within 5 min before reperfusion,respectively.After reperfusion,left ventricle myocardium samples were processed immediately in order to measure the activity of Na+ K+_ATPase and Ca2+_Mg2+_ATPase,endoxin level,intramitochondrial total calcium concentration and the experssion of α₁,α₂,α₃ and β₁ isoforms of sodium pump on mRNA and protein levels by RT-PCR and Western blotting and immunohistochemical assay,respectively.RESULTS: After MIR,the level of endoxin in myocardium was obviously increased.The activities of Ca2+_Mg2+_ATPase and Ca2+ Mg2+ ATPase in myocardial membrane were significantly decreased while intramitochondrial total calcium concentration increased.The gene expression of the α₁,α₂,α₃ and β₁ isoforms of sodium pump at both mRNA and protein levels were reduced markedly.Only the effect of verapamil on reducing intramitochondrial total calcium concentration was observed.Antidigoxin antiserum significantly reduced the level of endoxin in myocardium,restored the activities of Na+ K+_ATPase and Ca2+_Mg2+_ATPase,reduced intramitochondrial total calcium concentration,and up-regulated the expression of α₁,α₂,α₃ and β₁ isoforms of sodium pump at both mRNA and protein levels.CONCLUSION: MIR results in increase of endoxin secretion.The latter depresses the activity of Na+ K+_ATPase by down-regulating the gene expression of α₁,α₂,α₃ and β₁ isoforms of sodium pump in myocardial membrane,and also induces intramitochondrial calcium overload,thereby mediates MIR injury.     

Effects of Shenmai injection on acute myocardial ischemia/reperfusion injury in rats

AIM: To observe the effect of Shenmai injection on the acute myocardial ischemia/ reperfusion injury in rats. METHODS: The left-anterior coronary artery was ligated for 10 minutes and then loosed for 15 minutes to establish the animal model of acute myocardial ischemia/reperfusion injury. During the process, electrocardiogram was traced continuously to observe the arrhythmia caused by reperfusion. The levels of SOD, MDA, Na⁺, K⁺-ATPase and Ca²⁺ -ATPase in ventricular myocardium were measured. The mitochondria was observed through electron microscope. RESULTS: Shenmai injection decreased the incidence of arrhythmia caused by reperfusion and shortened its duration. Shenmai injection improved the activity of SOD, Na⁺, K⁺-ATPase and Ca²⁺ -ATPase, decreased the content of MDA in myocardium and relieved the injury of mitochondria. CONCLUSION: Shenmai injection had a protective effect on acute myocardial ischemia/reperfusion injury in rats. The mechanism may be related to relieving the injury caused by oxygen free radical and calcium overload.     

Dexamethasone pretreatment attenuates reperfusion arrhythmia in rats

AIM: To investigate the effect of dexamethasone (DEX) preconditioning on reperfusion arrhythmia. METHODS: 46 Sprague-Dawley rats were divided randomly into DEX and control (CON) group, the rats were pretreated with DEX or sodium chloride before their hearts were separated for Langendorff perfusion and for ischemia/reperfusion. The reperfusion arrhythmias were observed dynamically after 60 min reperfusion following 30 min ischemia. The expression of HSP72 in myocardium was examined by Western blotting and immunohistochemistry at reperfusion 60 min. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and the activities of Na+-K+-ATP ase, Ca2+-Mg2+-ATPase on myocardial plasma membrane were detected. RESULTS: Compared with control group, the accumulated points and persistence time of ventricular arrhythmia were reduced significantly in DEX group (P<0.05), the expression of HSP72 was significant upregulated (P<0.05), the level of MDA was reduced significantly, the activities of SOD, CAT, GSH-Px and Na+-K+-ATPase were significantly higher (P<0.05). CONCLUSION: Dexamethasone pretreatment markedly reduces the reperfusion ventricular arrhythmias in rats, which may be attributed to upregulation of HSP72, SOD, CAT, GSH-Px , Na+-K+-ATPase and inhibition of lipid peroxidation.     

NaCl胁迫对酸枣幼苗离子吸收与分配的影响

以酸枣水培幼苗为试验材料,研究了不同浓度NaCl胁迫对其活性氧、细胞膜透性、根系活力、不同器官Na+、K+、Ca2+和Mg2+离子含量的影响。结果表明：NaCl处理6 d,50、100 mmol ? L-1处理酸枣叶片无萎蔫症状,150、200 mmol ? L-1处理叶片萎蔫。在150、200 mmol ? L-1 NaCl处理下叶片H2O2积累增加,50、100、150、200 mmol ? L-1 NaCl处理下均有积累。随着NaCl处理浓度的升高,根、茎、叶中Na+含量均显著增加,叶片中K+、Ca2+和Mg2+含量显著下降,根和茎的K+和Mg2+含量变化不显著,Ca2+在200 mmol ? L-1NaCl处理下显著下降。根、茎、叶中K+/Na+、Ca2+/Na+、Mg2+/Na+均显著下降,但是根的K+/Na+值始终大于1。总之,NaCl胁迫下,维持根和茎中相对稳定的K+、Mg2+水平、保持根部K+/Na+比值 > 1,是酸枣幼苗对盐胁迫的一种适应。     

Up-regulation of miR-133a expression attenuates myocardial fibrosis in spontaneously hypertensive rats

AIM: To investigate the effect of up-regulated expression of microRNA-133a (miR-133a) on myocardial fibrosis in spontaneously hypertensive rats (SHR). METHODS: Wistar-Kyoto (WKY) rats with homologous normal blood pressure served as the normal control group. SHR were divided into SHR group, SHR+ adeno-associated virus (AAV) group and SHR+miR-133a-AAV group randomly. miR-133a carried by miR-133a-AAV was transfected into SHR heart by coronary perfusion. The rat tail artery pressure was monitored. The myocardial collagen deposition was observed by Masson staining. The expression of miR-133a in myocardial tissue was detected by real-time PCR. The protein levels of transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) were determined by immunohistochemistry and Western blot. RESULTS: Compared with the WKY rats, the tail artery pressure of the SHR increased significantly. The expression of miR-133a in heart decreased, and the expression levels of TGF-β1 and CTGF increased (P<0.05), and myocardial fibrosis occurred. After up-regulating the expression level of miR-133a in the heart of SHR, the myocardial fibrosis was significantly reduced, and the expression levels of TGF-β1 and CTGF decreased (P<0.05). CONCLUSION: Up-regulation of the miR-133a expression improves myocardial fibrosis induced by hypertension, which may be related to inhibiting the protein expression of TGF-β1 and CTGF in myocardium.     

Influence of ovariectomy and estrogen replacement on gene expression profile of myocardium in rats

AIM:To investigate the influence of ovariectomy and estrogen replacement treatment on profile of gene expression in myocardium by cDNA microarray,and to characterize the targeting genes of estrogen.METHODS:cDNA microarray containing 1 400 rat cDNAs was used to study the genes differentially expressed in myocardium between sham (Ⅰ),ovariectomy (Ⅱ,OVX) and estrogen replacement treatment (Ⅲ,OVX+E2) group.Then down-regulated genes in myocardium of OVX rats were further confirmed by RT-PCR.RESULTS:177 genes were differentially expressed in myocardium between sham and OVX rats,with 91 genes up-regulated and 86 genes down-regulated in OVX rats.164 genes were differentially expressed in myocardium between OVX and OVX+E2 rats,with 113 genes up-regulated and 54 genes down-regulated in OVX rats.There were 54 genes differentially expressed in OVX compared to sham and OVX+E2.They are involved in membrane channels and transporters (18),cell receptors (9),intracellular transducers/effectors/modulator (7) and metabolism (6).Most of the genes (45) were down-regulated in OVX rats and up-regulated in OVX+E2 rats.RT-PCR test confirmed the results of cDNA microarray.CONCLUSIONS:Long-term estrogen replacement may influence the expression of genes involved in membrane channels and transporters,cell receptors,intracellular transducers/effectors/ modulator and metabolism.Long-term estrogen replacement has some beneficial effects on ionic concentration and cardiac function which partially comes from the results of influence of expression on Na+,K+-ATPase and Na+/H+ exchanger.Estrogen has an inhibitory effect on the expression of dopamine receptor,which partially clarify the myocardial protection of estrogen.     

Effects of benazepril on cardiac function,free oxygen radicals,sarcoplasmic reticulum Ca2+-ATPase following cardiac ischemia-reperfusion in spontaneously hypertensive rats

AIM: To investigate the effects of angiotensin converting enzyme inhibitor (ACEI), benazepril (B), on cardiac function , free oxygen radicals, sarcoplasmic reticulum(SR) Ca²⁺-ATPase following ischemia-reperfusion in sportaneously hypertensive rats (SHRs). METHODS: Thirty 10-week-old female SHRs were randomly assigned into two groups: group SHR was control; The animal in group SHR+B was given with 10 mg/kg of benazepril per day. Another 15 Wistar rats with the same age and sex were normal control (group Wistar). After 12 weeks of pretreatment, all rats in each group were subjected to 30 min of left anterior descending coronary artery occlusion and 30 min of reperfusion. Hemodynamic parameters, left heart-to-body weight ratio (LVW/BW), myocardial malondialdehyde (MDA) concentration, superoxide dismutase (SOD) activity, and SR Ca²⁺-ATPase activity were measured. RESULTS: Compared to group Wistar, the rats in group SHR had higher blood pressure, LVW/BW and myocardial MDA concentration, more serious left cardiac function injury and lower myocardial SOD activity and SR Ca²⁺-ATPase activity; group SHR+B had lower myocardial MDA concentration, higher myocardial SOD activity, but no difference in blood pressure, LVW/BW, the degree of left cardiac function injury and myocardial SR Ca²⁺-ATPase activity. CONCLUSION: Benazepril can attenuate ischemia-reperfusion-induced cardiac function injury by regression of left ventricular hypertrophy (LVH), improving SR Ca²⁺-ATPase activity and decreasing oxygen free radicals injury in SHRs.     

Effects of 5-HT and electrolytes on the airway remodeling of bronchial asthma in guinea pigs

AIM: To explore the effects of 5-HT and electrolytes on the airway remodeling in guinea pigs with bronchial asthma.METHODS: 70 guinea pigs were divided into 7 groups: control group, model group, continued model group, 5-HT group, anti-5-HT group, high Mg2+ group, low Mg2+ group.Remodeling model was established with ovalbumin.RESULTS: ① In model group, 5-HT of serum and thickness of airway walls were significantly increased compared with control group (P<0.05,P<0.01).② In continued model group, 5-HT and thickness of airway walls were significantly increased compared with model group (P<0.05, P<0.01).③ In 5-HT group, thicknesses of airway walls were significantly increased compared with continued model group (P<0.05).④ In anti-5-HT group, thicknesses of airway walls were significantly decreased compared with continued model group (P<0.05).⑤ In high Mg2+ group, thicknesses of airway walls were significantly decreased compared with continued model group (P<0.05).⑥ In low Mg2+ group, thickness of airway smooth muscle was significantly increased compared with continued model group (P<0.05).⑦ With the aggravation or alleviation of airway remodeling, concentration of Ca2+ in serum was upward or downward.However, concentration of PO3-4 was downward or upward.⑧ Veriety of Na+, K+, Cl- was no significant difference among groups.⑨ Concentration of 5-HT in serum was corrected with that of Ca2+.CONCLUSIONS: ① 5-HT mediates airway remodeling of asthma in guinea pigs whereas Mg2+ may play a regulatory role.② Increase in Ca2+ and decrease in PO3+4 may promote the airway remodeling of asthma whereas Na+, K+, Cl- may not play any role.③ Concentration of 5-HT in serum was corrected with that of Ca2+ in airway remodeling of asthma.     

Dependence of adrenoceptor regulation on oxidative stress in cardiac injury induced by high sympathetic activity in rats

AIM：To investigate the dependence of the adrenoceptor regulation on oxidative stress in the rats with cardiac injury induced by high sympathetic activity. METHODS：Healthy SD rats were randomly divided into 7 groups: control, model, propranolol (Pro), prazosin (Praz), Pro+Praz, vitamin E (VE) and Pro+Praz+VE. The rats were intraperitoneally injected with norepinephrine (NE) for continuous 16 d to reproduce cardiac injury, and treated with the respective drugs. During the experimental process, the body weight was recorded. At the end of the experiments, the following parameters were measured: the ventricular remodeling indexes (cardiac index and hydroxyproline of the left ventricle), histopathologic examination, oxidative/antioxidative indexes ［MDA, SOD, catalase (CAT), GSH-Px and total antioxidant capacity (T-AOC)］, and energy metabolism (Na+-K+ ATPase and Ca2+-Mg2+ATPase). RESULTS：The increase of body weight in model group was significantly slower than that in control group after 9 d of treatment (P<0.05). The cardiac index and left ventricular hypertrophy were significantly increased. Oxidation/antioxidation and energy metabolism were disturbed. In Pro, Praz, Pro+Praz and VE groups, the body weight, cardiac index, left ventricular fibrosis and oxidative/antioxidative dysfunction were ameliorated. Pro, Praz and Pro+Praz increased the activity of Na+-K+ ATPase and Ca2+-Mg2+ATPase. Treatment with Pro+Praz showed the best result in all of the indexes (P<0.05). CONCLUSION：The dependence of adrenoceptor regulation plays an important role in the formation of oxidative stress in the process of rat cardiac injury induced by high sympathetic activity.