Effects of Ginkgo leaf extract and dipyridamole injection on tension of thoracic aorta rings of rats with hyperkalemia

AIM: To investigate the effects of Ginkgo leaf extract and dipyridamole injection (GD) on the tension of thoracic aorta rings isolated from hyperkalemia rats(HKR).METHODS: After the model of HKR was established and the preparation of the thoracic aorta rings was made, the tension of the rings was measured by a biological signal analytical system. The thoracic aorta rings were exposed to the medium containing GD at different concentrations and the vaso-constrictive tension was observed after stimulated with phenylephrine (PE) or KCl. RESULTS: Stimulated with PE or KCl, the tension of the thoracic aorta rings in HKR group was significantly higher than that in normal group (P<0.05). GD at the concentrations used in the experiment did not affect the basal tension in the resting rings prepared from both HKR and normal rats. In HKR group, pretreatment of the endothelium-intact thoracic aorta rings with GD at different concentrations showed no significant effect on KCl-induced vessel constriction (P>0.05). However, GD at the concentration of 16 mg/L significantly attenuated the vessel constriction induced by PE (P<0.05), which was inhibited by the pretreatment with N^ω-nitro-L-arginine methylester or methylene blue. GD at different concentrations did not show significantly inhibitory effect on PE-induced tension of endothelium-denuded thoracic aorta rings in HKR group (P>0.05). CONCLUSION: GD causes endothelium-dependent relaxation in the thoracic aorta rings of HKR. This effect may be mediated by the nitricoxide-guanylyl cyclase pathway.     

Effects of cholecystokinin octapeptide on changes in rabbit thoracic aortic reactivities induced by lipopolysaccharides in vitro

AIM and METHODS: To elucidate the mechanism of anti-endotoxic shock of cholecystokinin octapeptide(CCK-8), the effects of CCK-8 on changes in rabbit thoracic aortic reactivities induced by lipopolysaccharides(LPS) in vitro were studied, and the ultrastructure of the endothelial cells was observed under scanning electron microscope. RESULTS: Incubation of thoracic aortic rings(TARs) with LPS(100 mg/L) resulted in an time-dependent impairment of the endothelium-dependent relaxations to acetylcholine(incubation for 3, 7, 14 h), a reduction of contractive response to phenylphrine(incubation for 14 h) and ultrastructural injury in endothelial cells(incubation for 7 h), all of which were alleviated by concomitant incubation with CCK-8(1 mg/L). In contrast, neither the vascular contractions nor the relaxations were affected by CCK-8 (1 mg/L) alone. CONCLUSION: CCK-8 improved the vascular reactivities in the presence of LPS, which may be one of the anti-endotoxic shock mechanisms of CCK.     

Effects of butylphthalide on atherosclerosis lesion and VCAM-1 expression in aortic wall of ApoE-/- mice

AIM: To observe the protective effects of butylphthalide on atherosclerosis lesion and vascular cell adhesion molecular-1 (VCAM-1) expression in the aortic wall of ApoE^-/- mice, and to explore the possible mechanism underlying these beneficial effects.METHODS: Male ApoE^-/- mice at 6 weeks of age (n=90) were randomly divided into 3 groups. Thirty ApoE^-/- mice fed with high-fat diet and treated with saline simultaneously were defined as model group. Thirty ApoE^-/- mice fed with high-fat diet and treated with butylphthalide (100 and 200 mg·kg^-1·d^-1) were defined as treatment groups. Thirty wild-type C57BL/6J mice treated with saline were defined as control group. Fifteen mice in each group were sacrificed both at the ages of 18 and 30 weeks. The body weight, food intake and water intake were monitored weekly through the experiment. The lipid profiles were determined both at 18 and 30 weeks of age. Aortic roots were stained with hematoxylin and eosin for pathological examination. Serum ox-LDL, CRP, TNF-α and IL-6 were examined by ELISA. The expression of VCAM-1 at mRNA and protein levels was determinate by real-time PCR and Western blot in the thoracic aortas. RESULTS: Compared with control group, at 18 and 30 weeks of age, the body weight, serum lipid profiles and inflammatory factors were increased, while the atherosclerotic plaques were raised. The mRNA and protein levels of VCAM-1 were up-regulated. However, serum lipid levels in butylphthalide treatment groups (both at doses of 100 and 200 mg·kg^-1·d^-1) were decreased significantly. Serum ox-LDL, CRP, TNF-α and IL-6 were also decreased by butylphthalide treatment. Furthermore, atherosclerotic plaque areas in the aortic roots were reduced by butylphthalide treatment. In addition, the expression of VCAM-1 at mRNA and protein levels in the thoracic aortas was down-regulated by butylphthalide treatment.CONCLUSION: Butylphthalide delays the occurrence of high-fat diet-induced atherosclerosis and down-regulates the expression of VCAM-1 in the ApoE^-/- mice, which may be due to its alleviative effects on hyperlipidemia and inflammation.     

Effects of amifostine on formation of abdominal aortic aneurysm in mice induced by benzo[a] pyrene

AIM: To study the role of amifostine on the formation of benzo[a]pyrene (BaP)-induced abdominal aortic aneurysm (AAA) in C57BL/6J mice and the underlying mechanism. METHODS: RAW246.7 mononuclear macrophage in vitro were divided into control group, DMSO group, BaP group, low dose (1 μmol/L) amfostine treated group, middle dose (5 μmol/L) amfostine treated group and high dose (25μmol/L) amfostine treated group. The influence of BaP on the expression of matrix metalloproteinase (MMP)-9, MMP-12, TNF-α, NF-κB in the RAW246.7 mononuclear macrophages in vitro was determined by Western blot. Male C57BL/6J mice (8 months old) were divided into control group, model group (AngII+BaP group), low dose (50 mg/kg) amfostine treated group and high dose (100 mg/kg) amfostine treated group. After 6 weeks, the abdominal aorta were isolated. The aortic tissues were subjected to HE and Masson staining. The vascular wall structure, infiltration of macrophage, the expression of MMP-9, MMP-12, TNF-α, NF-κB were evaluated by Western blot and immunochemistry staining. RESULTS: Amifostine attenuated BaP-induced expression of TNF-α, MMP-9, MMP-12, NF-κB in the RAW246.7 mononuclear macrophages (P<0.05). The results of animal experiments showed that the incidence of AAA in high dose amifostine treated group were significantly lower than that in low dose amifostine treated group and model group (P<0.05). Immunohistochemistry staining observation showed that amifostine inhibited the aortic macrophage infiltration more obviously in high amifostine treated group compared with model group and low dose amifostine treated group (P<0.05). Compared with model group and low dose amifostine treated group, the MMP-9, MMP-12, TNF-α and NF-κB expression of abdominal aorta in high amifostine treated group was reduced significantly (P<0.05). CONCLUSION: Amifostine inhibits BaP-induced activation of macrophages, and also prevents the formation of abdominal aortic aneurysm in C57BL/6J mice induced by BaP by inhibition of the NF-κB pathway, macrophage infiltration and the expression of TNF-α and MMPs.     

Effect of insulin on the secretion of VEGF and its receptor in serum-free cultured bovine thoracic aortic endothelial cells

AIM: This study was designed to investigate the secretion of VEGF and its receptor (flt-1 or flk-1/KDR) protein by cultured bovine thoracic aortic endothelial cells treated with various insulin concentrations. METHODS: Endothelial cells was isolated from bovine thoracic aorta, and cultured in serum-free medium, then incubated with different insulin concentrations (30 mU/L, 300 mU/L, 3 000 mU/L). The level of VEGF and its receptor (flt-1 or flk-1/KDR) protein were detected by immunohistochemical staining. RESULTS: As compared with no insulin group, the expression of VEGF protein in low insulin concentration (30 mU/L and 300 mU/L) groups were significantly increased (P＜0.01). The expression of VEGF protein in high insulin concentration (3 000 mU/L) group was significantly decreased (P＜0.05). Howerer, no difference of the expression of VEGF receptor (flt-1 or flk-1/KDR) protein among all groups (P＞0.05) was observed. CONCLUSION: Low concentration insulin up-regulates the VEGF protein expression while high concentration insulin down-regulates the VEGF protein expression in bovine thoracic aortic endothelial cells, but insulin had no directly effect on the VEGF receptor (flt-1 or flk-1/KDR) protein expression in bovine thoracic aortic endothelial cells.     

Protective effect and the possible mechanism of Nano-Se on myocardium of experimental diabetes mice

AIM: To observe the protective effect of Nano-Se on myocardium of experimental diabetes mice. METHODS: Sixty healthy male KM mice were chosen, ten of which were selected randomly as the normal control group. After fasted for 24 h, the rest 50 mice were injected with streptozotocin (STZ, 50 mg/kg) intraperitoneally for 5 d. At 7th d, the blood-sugar was measured from vena caudalis, 40 mice, of which blood-sugar exceeded 16.65mmol/L, were selected and randomized into 4 groups: the positive control group, low dose (25 μg/kg) Nano-Se group, mid dose (50 μg/kg) Nano-Se group, high dose (50 μg/kg) Nano-Se group. All mice were given intragastric administration of 0.2 mL normal saline and corresponding dose of Nano-Se. The body weights were measured every week, and the dose of which was adjusted according to the change of the body weights. 8 weeks later, the mice were killed and cardiac muscle of the left ventricle was taken. The myocardium was prepared to 10% homogenate for measuring SOD, GSH-Px activity and MDA content. The myocardial cell apoptosis was measured by TUNEL. The expressions of Bc1-2 and Bax proteins were determined by immunohistochemistry. RESULTS: Compared to normal group, the SOD and GSH-Px activities in positive control group decreased, MDA level increased, the rate of myocardial cell apoptosis increased significantly, Bc1-2 protein expression deceased and Bax protein expression increased. Compared to positive control group, the SOD and GSH-Px activities in low and mid dose Nano-Se groups expression increased, MDA level decreased, myocardial cell apoptosis rate decreased, Bc1-2 protein expression increased and Bax protein expression decreased. Moreover, the SOD and GSH-Px activities in high dose Nano-Se group decreased obviously compared to those in mid dose Nano-Se group. MDA level and myocardial cell apoptosis rate increased, Bc1-2 protein expression decreased and Bax protein expression increased, no significant difference in SOD, GSH- Px activity, MDA level and myocardial cell apoptosis rate was observed compared with positive control group. CONCLUSION: The damage of cardiac muscle is alleviated when a certain dose of Nano-Se is supplied to diabetes mice. The protective mechanism may be related to antioxidation, blood-sugar adjustment and the increase of Bc1-2 expressing.     

Effects of aging on sperm maturation and fertility in mice

AIM: To investigate the effects of aging on sperm maturation and fertility in mice. METHODS: Sperm of caput epididymides and cauda epididymides were obtained from Kunming mice aged 6 months (n=15, as control) and 18 months (n=15). Sperm parameters including sperm density, viability, motility and normal morphological rate were recorded. Sperm of cauda epididymides was observed by transmission electron microscope. The fertility potential and embryo developmental competence were performed by in vitro fertilization and embryo culture. RESULTS: Sperm motility, density and normal morphological rate in aged mice were lower than those in control (P<0.05). The fertilization rate and embryo developmental rate of aged group were significantly lower than those in control (P<0.01). CONCLUSION: Aging influences spermatogenesis in testes and sperm maturation in epididymides. Mouse would be served as a good model for male reproductive aging research.     

Effects of phytosterol ester on aortic aging and expression of related genes in rats

AIM: To explore the protective effect of phytosterol ester (PSE) on aortic aging in rats. METHODS: The female SD rats (12 months old, n=42) were randomly divided into control group, model group and PSE group. During the experiment, the rats in control group, model group and PSE group were treated with basic feed, high-fat diet (HFD) and HFD with 2% PSE (W/W) for 6 months, respectively. The morphological changes of the aorta were observed by HE staining and Masson staining, and the absolute area of smooth muscle cells and collagen fiber in the vascular wall were measured by image analysis. The levels of advanced glycosylation end products (AGEs), malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) in the plasma were detected. The expression of silent information regulator 1 (SIRT1) and peroxisome proliferator-activated receptor γ (PPARγ) at mRNA and protein levels in the vascular tissue was determined by real time PCR and Western blot, respectively. RESULTS: PSE significantly lowered plasma TC and LDL-C, and increased plasma HDL-C level (P<0.05), but had no effect on plasma TG level. PSE significantly attenuated the thickening of intima and media of aging aortic, and decreased the migration of vascular smooth muscle cells (VSMC) and the amount of VSMC and collagen fiber in the aorta (P<0.05). PSE significantly reduced the contents of AGEs and MDA (P<0.05), but had no effect on the activity of SOD and CAT in the plasma. PSE also down-regulated the expression of PPARγ and up-regulated the expression of SIRT1 (P<0.05). CONCLUSION: PSE is able to attenuate the senescence process in the aorta by reducing the production of reactive oxygen species in plasma, and activating SIRT1, or inhibiting the expression of PPARγ in vascular tissues.     

Role of nitric oxide in the inhibition of lipopolysaccharide-induced thoracic aortic hyporeactivity by cholecystokinin in vitro

AIM:To investigate the effect of cholecystokinin octapeptide(CCK-8) on the L-arginine-nitric oxide(NO) pathway in rabbit thoracic aortae treated with lipopolysaccharide(LPS).METHODS:The isolated thoracic aortic rings(TARs) from rabbits were incubated with LPS, LPS+CCK or vehicle for 14 h. Then the contractility to phenylephrine(PE) by TARs and the response to L-arginine(L-Arg) by pre-contractile TARs were measured. In addition, we added NO synthase(NOS) inhibitors aminoguanidine(AG)and N^ω-nitro-L-arginine(L-NNA) into organ baths to observe the changes of vascular contractility to PE. NOS activity in isolated TARs were also detected. RESULTS:Incubation of TARs with LPS for 14 h resulted in an increase of NOS activity and a reduction of contractility to PE. Treatment with CCK-8 significantly inhibited the increased NOS activity in thoracic aortae and improved the hypocontractility of TARs to the same degree as AG.CONCLUSION:CCK-8 may improve the hypocontractility of TARs induced by LPS by inhibiting the activity of NOS.     

Synergistic effect of hypertension and type 2 diabetes on cardiac dysfunction and myocardial remodeling in mice

AIM: To investigate whether the effect of hypertension combined with diabetic can lead to cardiac dysfunction and myocardial remodeling in mice. METHODS: The diabetic mice and non-diabetic mice of 14 weeks old were administered with PBS or angiotensin II (Ang II) for 4 weeks to induce mild hypertension. The left ventricular (LV) function was assessed by echocardiography and dobutamine stress test. The LV tissues were subjected to HE staining to assess cardiac hypertrophy. The phospharylated adenosine monophosphate-activated protein kinase (p-AMPK) levels in the LV tissues were determined by Western blotting. RESULTS: Compared with control group, diabetic mice (DM group) neither displayed marked cardiac dysfunction nor myocardial remodeling. Ang II treatment did not affect body weight and glucose level, but the blood pressure was increased in the diabetic and control mice. Ang II-induced LV hypertrophy in diabetic mice was significantly higher than that in control mice as assessed by LV masses and cardiomyocyte sizes. Moreover, Ang II-treatment reduced LV fractional shortening and contractility in the diabetic mice, but not in the control mice. The p-AMPK levels were significantly reduced in Ang II group, DM group and DM+Ang II group. CONCLUSION: The cardiac function and cardiac structure of type 2 diabetic mice did not obviously change. Cardiac dysfunction and myocardial remodeling were easily induced in type 2 diabetic mice when hypertension happened, suggesting that hypertension is a critical factor of cardiac dysfunction and myocardial remodeling in type 2 diabetic mice.     

Effects of berberine and yohimbine on splenocyte apoptosis in septic mice

AIM: To observe the effects of berberine and yohimbine on splenocyte apoptosis in septic mice and underlying mechanisms. METHODS: The mice were subjected to cecal ligature and puncture (CLP). The drugs or vehicle were given intragastrically 2 h after the surgery according to the following 5 groups: sham, CLP, CLP+berberine, CLP+yohimbine, and CLP+berberine+yohimbine. The apoptosis of splenocytes stained by TUNEL was observed under laser scanning confocal microscope 20 h after CLP. The splenic lymphocytes were isolated and observed using flow cytometry. The activities of caspase-3, caspase-8 and caspase-9 in splenic lymphocytes were detected, and the expression of Fas, Bim, Bcl-2 and Bax in the splenocytes was also determined by Western blotting. RESULTS: The TUNEL staining showed that the apoptotic rate of the splenocytes in septic mice 20 h after CLP was significantly higher than that in sham and CLP+yohimbine groups (P＜0.05). Compared with CLP group, the proportion of apoptotic cells was decreased in septic mice in CLP+berberine+yohimbine and CLP+yohimbine groups (P＜0.05). Flow cytometry analysis demonstrated the similar results in the apoptosis of splenocytes and T lymphocytes. However, only yohimbine treatment reduced the apoptosis of B lymphocytes in the spleen of sepsis-challenged mice. Compared with CLP group, caspase-9 activity was significantly reduced in CLP+berberine group (P＜0.05), the activities of caspase-3, caspase-8 and caspase-9 were all statistically reduced (P＜0.05) in CLP+yohimbine group and CLP+yohimbine+berberine group. CLP significantly increased the expression of cytosolic Fas, Bim and mitochondrial Bax in the splenocytes, and decreased Bcl-2 expression compared with sham group. Compared with CLP group, the expression of cytosolic Bim and mitochondrial Bax in CLP+berberine group were reduced (P＜0.05). Fas expression decreased only in CLP+yohimbine group (P＜0.05). Berberine combined with yohimbine reduced the expression of cytosolic Fas, Bim and mitochondrial Bax in the septic mouse splenocytes (P＜0.05).CONCLUSION: Yohimbine reduces sepsis-induced splenic lymphocyte apoptosis in mice by inhibiting Fas expression and in turn blocking both extrinsic and intrinsic apoptosis pathways. Berberine reduces Bim expression and inhibits caspase-9 activation, but not caspase-3 activation and apoptosis in the septic mouse splenocytes. Berberine combined with yohimbine reduces splenocyte apoptosis in the septic mice by inhibiting both extrinsic and intrinsic apoptotic pathways.     

Effects of IGFBPrP1 and thioacetamide on liver tissues in mice

AIM: To investigate the effects of insulin-like growth factor binding protein related protein 1(IGFBPrP1) and thioacetamide (TAA) on the liver tissues, and to identify the role of IGFBPrP1 in liver fibrosis. METHODS: Thirty-two male C57BL/6 wild-type mice were randomly divided into 4 groups (n=8 in each group): control group, recombinant murine IGFBPrP1(rmIGFBPrP1) 4 weeks group, TAA 2 weeks group and TAA 4 weeks group. The methods of hematoxylin-eosin (HE) staining, picric acid-Sirius red staining, immunohistochemistry and Western blotting were performed. RESULTS: The extensive fatty degeneration of liver cells in rmIGFBPrP1 4 weeks group was observed. The collagen deposition was found in TAA 2 weeks group. In TAA 4 weeks group, the degree of hepatic fibrosis was more serious than that in TAA 2 weeks group. The expression levels of IGFBPrP1, transforming growth factor beta 1(TGF-β₁), Smad3, p-Smad2/3, collagen Ⅲ, collagenⅠand fibronectin (FN) in liver tissues were higher in rmIGFBPrP1 4 weeks group, TAA 2 weeks group and TAA 4 weeks group than those in control group. No significant difference of the expression levels of IGFBPrP1, collagen I and FN between rmIGFBPrP1 4 weeks group and TAA 2 weeks group was observed. CONCLUSION: IGFBPrP1 plays an important role in the process of thioacetamide-induced liver fibrosis. Meanwhile, IGFBPrP1 induces excessive deposition of extracellular matrix through TGF-β₁/Smad3 pathway.     

Change of shear stress in hypertriglycerlipidemic patients and the impact on endothelium-dependent relaxation

AIM: To investigate the profile of shear stress in hypertriglycerlipidemic patients and the impacts of fenofibrate on vascular endothelial function. METHODS: 62 hypertriglycerlipidemic patients were randomized into two groups (30 with low-fat diet treatment, 32 with fenofibrate) compared with 20 normal controls. Vessel structure, hemodynamic index and endothelium-dependent vasodilation of brachial artery were assessed by B-mode ultrasound imager. Serum NO, Ox-LDL, TC, TG, LDL-C, HDL-C were measured. RESULTS: Compared with controls, hypertriglycerlipidemic patients showed higher mean circumferential wall tension(MCWT) and lower mean shear rate(MSR), flow mediated dilatation(FMD) and Da, Dr. They had higher level of Ox-LDL and lower level of NO. NO was positive correlated with MSR, FMD and inversely correlated with TG, TC, LDL-C, Ox-LDL. 8 weeks of low-fat diet reduced TC and TG, but made no difference in NO, Ox-LDL and ultrasonic images. On the other hand, 8 weeks of fenofibrate treatment not only reduced TG, TC, LDL-C and Ox-LDL, but also elevated NO, MSR and FMD. CONCLUSION: The endothelial impairment of hypertriglycerlipidemic patients might be caused by lower level of MSR as well as oxidative substance such as Ox-LDL, which could inactivate NO and result in descent of endothelium-dependent relaxation. Elevation of MSR and elimination of Ox-LDL may improve endothelium-dependent relaxation.     

Effects of bFGF and insulin on proliferation of mice cartilage tissue cells

AIM:To explore the effects of basic fibroblast growth factor ( bFGF) and insulin on the cell proliferation and differentiation in primary cartilage cells. METHODS:After induction with different concentrations of bFGF and insulin, cell proliferation was measured with WST-1 method and fluoroscope methods. RESULTS:bFGF and insulin exerted their related action on primary cartilage cells in 0.4% fatal bovine serum at different concentrations. 25 μg/L bFGF and 5 mg/L insulin promoted cell proliferation significantly. CONCLUSION:bFGF and insulin prolong the survival time and promote cell proliferation in primary cartilage cells.     

PPARγ gene and protein expression in aortic plaque of different week-old apoE-knock out mice and the relationship with the composition of aortic plaque

AIM: To investigate the relationship of PPARγ gene expression with the composition of aortic plaque in apoE-knock out mice. METHODS: PPARγ gene and protein in aortic area of 20-week-old and 40-week-old apoE-knock out mice were investigated using RT-PCR and immunoblotting. The same aged wild type mice (C57BL/6J) were served as control (n=10). The composition of aortic plaques was analyzed by Movat method and oil red O staining. The expression of antigens such as PPARγ, SM-actin and MOMA-2 in aortic plaque were compared using immunohistochemistry. The relationship of PPARγ with macrophage, smooth muscle cells (SMC), lipid, elastic fiber, collagen and proteoglycan in aortic plaque were analyzed using immunofluorescence. RESULTS: PPARγ gene and protein in aortic wall and plaque of apoE-knock out mice were more significant than that in the same aged C57BL/6J mice (P<0.05). PPARγ expression at 40-week-old apoE-knock out mice was most significant and very low in C57BL/6J mice. More PPARγ expression of gene and protein at 20-week-old C57BL/6J mice than 40-week-old C57BL/6J mice were observed. Compared with 20-week-old apoE^-/- mice, the lipid pool in aortic plaque at 40-week-old apoE^-/- mice were increased remarkably, while elastic fiber, collagen and proteoglycan in plaque were decreased and aortic remodeling was very significant. Even, upregulation of MOMA-2 and downregulation of SM-actin were also detected in latter (P<0.05). In addition to SMC of aortic tunica media, PPARγ also expressed in SMC and macrophages in the aortic plaque of apoE^-/- mice. PPARγ was very enriched in lipid pool of the plaque. CONCLUSION: PPARγ expression level decreases with aging in C57BL/6J mice, while increases with plaque progression in apoE-knock out mice. There is positive correlation between PPARγ expression and lipid composition in plaque. The observed upregulation of PPARγ gene expression in aortic plaque may be a compensatory behavior and protective mechanism in apoE-knock out mice.     

Effects of taurine-zinc on learning and memory abilities of vascular dementia mice

AIM:To observe the effects of taurine-zinc (TZC) on the learning and memory abilities of vascular dementia (VD) mice and to investigate the related mechanism. METHODS:The mice were randomly divided into model group, sham group, and TZC at 50 mg/kg, 100 mg/kg and 200 mg/kg groups. The mice in drug groups were given TZC by gavage at 10 mL/kg once daily. The mice in sham group and model group were given equal volume of distilled water. VD mice were established by intercepting both common carotid arteries and bleeding at caudal vein after 14 d of gavage. The levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were detected by ELISA. The levels of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) were measured via spectrophotometer. Step-down test and Morris water maze test were used to examine the abilities of learning and memory in the mice. RESULTS:TZC at 50 mg/kg, 100 mg/kg and 200 mg/kg reduced the levels of TNF-α, IL-1β, iNOS and NO in the brain tissues. In the water maze test, TZC at 100 mg/kg and 200 mg/kg significantly decreased the error times and latency compared with model group. In the step-down test, the escape latency was prolonged and error times were lowered significantly by treatment with TZC at 50 mg/kg, 100 mg/kg and 200 mg/kg as compared with model group. CONCLUSION:TZC improves the abilities of learning and memory, which might be related to the reduction of TNF-α, IL-1β, iNOS and NO levels in VD mice.     

Changes of potassium channels in thoracic aorta of streptozotocin-induced diabetic mice in early stage

AIM:To investigate the changes of potassium channels in thoracic aorta of streptozotocin-induced diabetic mouse in the early stage of diabetes mellitus.METHODS:The effects of 60 mmol/L KCl, phenylephrine (PE), sodium nitroprusside (SNP) were measured and concentration-response curves to SNP were determined in the presence and in the absence of the inhibitors of potassium channels on the thoracic aortic rings of diabetic and age-matched control mice in vitro. RESULTS:STZ-diabetic mice showed a significant increase in the maximum contractile response and sensitivity of thoracic aorta to 60 mmol/L KCl and PE. The endothelium-independent relaxation response to SNP was increased by diabetes and were decreased significantly by pretreatment of the vessels with 1 mmol/L tetraethylammonium (TEA), 1 mmol/L 4-aminopyridine (4-AP) and 10 μmol/L glibenclamide in diabetes thoracic aorta. Only 4-AP decreased relaxation response to SNP in age-matched control mice. The -logIC₅₀ difference of TEA in thoracic aorta rings of diabetes was significantly higher than age-matched control mice.CONCLUSION:In early stage of diabetes mellitus, the opening or expression of K_Ca channels is significantly enhanced.The opening of K_ATP channels is also enhanced in this stage.     

Effects of sevoflurane preconditioning on myocardial dysfunction in lipopolysaccharide-challenged mice

AIM:To investigate the effects of sevoflurane(Sevo) preconditioning on myocardial dysfunction in lipopolysaccharide(LPS)-challenged mice. METHODS:Forty male BALB/c mice were randomly allocated to 4 groups:control group, LPS group, Sevo+LPS group and Sevo group. Following pretreatment with or without 2% Sevo for 30 min and washing out for 10 min, all mice received intraperitoneal injection of LPS or normal saline(NS). The mice received an echocardiographic evaluation by a high-resolution in vivo imaging system 12 h after administration of LPS or NS. The mice were then killed and the hearts were removed for histological analysis. Serum levels of lactic dehydrogenase(LDH), creatine kinase-MB(CK-MB) were measured with an automatic biochemical analyzer. The myocardium was homogenized for detecting the activity of inducible nitric oxide synthase(iNOS) and the content of nitric oxide(NO). RESULTS:Echocardiographic evaluation demonstrated that LPS resulted in an increase in lert ventricular end-diastolic volume and significant decreases in stroke volume,cardiac output and ejection fraction. The alteration of cardiac functions was inhibited by the pretreatment with Sevo. LPS caused significant elevation of LDH and CK-MB in serum samples and severe pathological damage of the hearts. Compared with LPS group, serum levels of LDH and CK-MB were reduced and pathological damage was attenuated in Sevo+LPS group. Sevo preconditioning also significantly attenuated the increases in iNOS and NO induced by LPS. CONCLUSION:Sevo preconditioning protects against myocardial impairment and myocardial dysfunction in LPS-challenged mice. Inhibition of iNOS activity and of NO production by Sevo preconditioning may contribute to the beneficial role in the process of cardioprotection during endotoxemia.     

草莓CIPK基因家族的鉴定与表达分析

从拟南芥数据库中获得CIPK基因家族注册号,运用生物信息学分析的方法,在蔷薇科森林草莓(Fragaria vesca)数据库中得到CIPK基因家族成员19个,可分为6个亚族。该基因家族分布在草莓7条染色体中的6条上。其编码蛋白的氨基酸数157～1 196,理论等电点3.91～9.34,分子量18 667.68～133 714.31 D。基因结构分析表明,有11条基因只有1个外显子,其余基因外显子数2～15。亚细胞定位结果表明,该基因家族成员主要在细胞质、细胞核和叶绿体上表达。蛋白质二级结构预测表明,该基因家族成员主要以α–螺旋、β–转角和不规则卷曲为主。对上游2 kb区域启动子顺式作用元件分析表明,该基因家族成员对逆境胁迫应答MYB响应明显,除FvCIPK02、FvCIPK15、FvCIPK17外,其他基因均对脱落酸应答元件ABRE响应明显。qRT-PCR数据分析表明,FvCIPK16、FvCIPK10和FvCIPK09分别在PEG、ABA和NaCl处理下,草莓试管苗中的相对表达量最高,分别是对照的18.4倍、29倍、13倍,说明FvCIPK16强响应干旱胁迫,FvCIPK10强响应A...     

Effects of ClC-3 over-expression on structure and function of thyroid in mice

AIM: To study the effect of ClC-3 gene over-expression on thyroid structure and function in mice.METHODS: Three-months-old FVB mice were used to study the difference of thyroid structure and function between wild-type (WT) mouse and ClC-3 transgene mice. The expression and distribution of ClC-3 in the thyroid of mice were determined by the methods of qPCR, Western blot and immunofluorescence. Behavioral monitoring was performed on the daily activities of mice. Serum concentrations of total triiodothyronine (TT3), total thyroxine (TT4) and thyrotropin (TSH) were measured by ELISA.RESULTS: Compared with the WT group, the expression of ClC-3 in the thyroid of ClC-3 transgene group was significantly increased (P<0.05). The thyroid gland showed obvious hyperplasia and the folliculi glandulae thyreoideae was significantly bigger in ClC-3 transgene mice (P<0.05). The weight loss was increased in ClC-3 transgene mice (P<0.05). The expression of TT3 and TT4 were significantly higher than that of WT group (P<0.05), but the change of TSH was not obvious.CONCLUSION: ClC-3 over-expression results in thyroid hyperplasia and thyroid hormone secretion. This study suggests that ClC-3 is likely to be involved in the synthesis of thyroid hormones.