Injection Of Same Amount Research Articles

Effect of electroacupuncture on myocardial transient receptor potential channels in mice with myocardial hypertrophy.

To observe the effect of electroacupuncture (EA) at "Neiguan"(PC6) on cardiac function, cardiac morphology and transient receptor potential channel (TRPC) protein expressions in myocardial tissue of mice with myocardial hypertrophy, so as to explore its mechanisms underlying improvement of myocardial hypertrophy. Forty-five male C57BL/6 mice were randomly divided into control, model and EA groups (15 mice/group). The myocardial hypertrophy model was established by subcutaneous injection of isoproterenol hydrochloride (15 mg·kg-1·d-1) for 14 days. The mice of the control group received subcutaneous injection of same amount of normal saline. The mice of the EA group received EA stimulation (frequency of 2 Hz, intensity of 1 mA) of bilateral PC6 for 20 min each time, once a day for 14 consecutive days. After the intervention, the body weight, tibia length and heart weight were measured. The left ventricular ejection fraction (EF), fractional shortening index (FS), left ventricular end-systolic volume (LVEV), left ventricular end-systolic internal diameter (LVID) and left ventricular posterior wall thickness (LVPW) were measured by using echocardiography for evaluating the cardiac function. The mean number and surface area of myocardial cells was detected by wheat germ agglutinin (WGA) staining, and changes of the cardiac morphology were observed under light microscopy after HE staining. The expression levels of TRPC1, TRPC3, TRPC4 and TRPC6 (TRPC1/3/4/6) in the myocardial tissue were detected by real-time quantitative PCR (qPCR) and Western blot, separately. Compared with the control group, the heart-body weight ratio(P<0.05) and heart-weight-to-tibia-length ratio (P<0.01), LVEV and LVID levels, the relative surface area, left ventricular area ratio, and the expression levels of cardiac TRPC1/3/4/6 were significantly increased (P<0.01, P<0.05), while the EF, FS, LVPW, number of cardiomyocytes, and the left ventricular posterior wall ratio were obviously decreased (P<0.01, P<0.05) in the model group. In comparison with the model group, the heart/body weight ratio, heart-weight-to-tibia-length ratio, LVEV and LVID levels, relative surface area, left ventricular area ratio, and the expression levels of cardiac TRPC1/3/4/6 were significantly decreased (P<0.01, P<0.05), while the EF, FS, LVPW, number of cardiomyocytes and left ventricular posterior wall ratio were significantly increased (P<0.01, P<0.05) in the EA group. H.E. staining showed disordered arrangement of cardiomyocytes and obvious myocardial interstitial inflammatory cell infiltration in the model group, and evident reduction of degree of cardiac fibrosis and interstitial edema in the EA group. EA of PC6 can improve the cardiac function and cardiac morphology in mice with myocardial hypertrophy, which may be related to its functions in down-regulating the expression of transient receptor potential channels.

The renal protective effect and mechanism of liraglutide in diabetic mice induced by high-fat diet

Objective: To investigate the protective effect of liraglutide on kidney of diabetic mice induced by high-fat diet and its possible mechanisms. Methods: C57BL/6J male mice were randomly divided into normal chow diet (NC) group and high-fat diet (HFD) group, which were fed with normal chow diet and HFD for 12 weeks respectively. After diet challenge, the mice were randomly divided into normal control group, normal chow diet with liraglutide treatment (NC+Lira) group, HFD group and high-fat diet with liraglutide treatment (HFD+Lira) group. The mice in NC+Lira and HFD+Lira groups were given intraperitoneal injection of liraglutide (400 μg·kg(-1)·d(-1)) for 8 weeks, while mice in NC and HFD groups were given intraperitoneal injection of same amount of normal saline. Urinary albumin and creatinine levels were measured by enzyme-linked immunosorbent assay (ELISA). Renal morphology was observed by HE staining. The expression levels of silent mating type information regulation 2 homolog 1 (SIRT1) and thioredoxin-interacting protein (TXNIP) were determined by Western blot. Results: Compared with HFD group, liraglutide significantly lowered the body weight [(30.98±1.29) g vs (39.43±2.58) g], fasting blood glucose (FBG) [(7.21±0.15) mmol/L vs (9.55±0.29) mmol/L] and urinary albumin/creatinine ratio (ACR) [(205.48±17.14) μg/mg vs (319.86±34.14) μg/mg] in HFD+Lira group (all P<0.05). HE staining showed that glomerular hypertrophy of HFD group alleviated after liraglutide treatment. The expression level of TXNIP in the kidney of HFD mice significantly decreased after liraglutide treatment (0.41±0.10 vs 3.50±0.70), while expression level of SIRT1 significantly increased (0.75±0.15 vs 0.32±0.04) (both P<0.05). Conclusion: Liraglutide could improve diabetic nephropathy by up-regulation of SIRT1 expression and down-regulation of TXNIP expression in diabetic mice induced by HFD.

Allicin improves cardiac function by protecting against apoptosis in rat model of myocardial infarction.

To study the effects of allicin on cardiac function and underlying mechanism in rat model of myocardial infarction (MI). Ninety-four Wistar rats were randomly assigned to 6 groups (n=14-16 per group): sham control group [underwent thoracotomy without left anterior descending (LAD) occlusion and only received an injection of the same amount of citrate buffer], MI control group (subjected to LAD occlusion and only received an injection of same amount of citrate buffer), positive control group (subjected to LAD occlusion and received an injection of diltiazem hydrochloride at the dose of 1.5 mg/kg), and MI + allicin groups (subjected to LAD occlusion and received an injection of allicin at the doses of 1.2, 1.8, and 3.6 mg/kg). All of the drugs were administered intraperitoneally daily for 21 days. The infarct area was measured by myocardial staining. Hematoxylin-eosin staining was used to observe the pathological changes. Cardiac function parameters were assessed by echocardiography. The myocardial apoptotic index was estimated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining. The expression of Bax and Bcl-2 were detected by quantificational real-time polymerase chain reaction and Western blot. Treatment with allicin could attenuate the myocardial infarct area (P<0.05) and relieve the changes of the myocardium. The left ventricular anterior wall diastolic and systolic thicknesses were increased in the allicin-treated groups (P<0.05), while there was no signifificant difference in the left ventricular posterior wall diastolic and systolic thickness (P>0.05). The left ventricular internal diameter in systole, ejection fraction, fractional shortening, and stroke volume were dramatically elevated in allicin-treated rats (P<0.05). Allicin dose-dependently reduced creatine kinase and lactate dehydrogenase levels (P<0.05). The myocardial apoptotic index was also markedly lowered, and Bax expression was signifificantly decreased, whereas Bcl-2 expression exhibited an opposite trend in allicin-treated rats (P<0.05). Allicin appears to exert a cardioprotective effect that may be linked to blocking Bcl-2/Bax signaling pathway-denpendent apoptosis, further improving cardiac function.

The role of heme oxygenase-1 in the protection of chronic intermittent hypoxia-induced lung injury in vivo

To investigate the effect of chronic intermittent hypoxia (CIH) on inflammatory and pathological changes of the lung in an animal model as well as the protective effect of heme oxygenase-1 in this process. Twenty-four Male Sprague-Dawley rats were randomly divided into 4 groups: intermittent normoxia (IN) group, CIH group, IN+hemin injection (hemin) group and CIH+hemin injection (CIH+hemin) group. The CIH profiling was repetitive 4 min 10% O₂and 2 min 21% O₂for 8 hours per day for 6 weeks. Animals exposed to IN were kept in an identical chamber receiving intermittent air at the same flow rate. Hemin was intraperitoneally injected (4 mg/kg) to induced HO-1 expression, and other 2 groups only received an injection of same amount of saline. Western blot was utilized to detect the pulmonary HO-1 expression levels and ELISA was used to examine the pulmonary cytokine levels. H&E staining was used to investigate pathological changes of the lung. CIH significantly induced HO-1 expression in the lung and hemin induced a synergistic increase of HO-1 expression. CIH exposure significantly increased pulmonary inflammatory cytokines levels, TNF-α [(2.20 ± 0.10) vs (1.80 ± 0.08) ng/ml], IL-6 [(0.87 ± 0.05) vs (0.52 ± 0.05) ng/ml], CINC-1 [(66 ± 6) vs (39 ± 5) pg/ml] and MCP-1 [(2.20 ± 0.09) vs (1.40 ± 0.10) ng/ml], accelerated cell apoptosis and induced pathological changes of the lung, while hemin could inhibit the elevation of cytokines [(TNF-α:(1.60 ± 0.20) ng/ml, IL-6: (0.60 ± 0.07) ng/ml, CINC-1: (45 ± 6) pg/ml, MCP-1: (1.80 ± 0.10) ng/ml, all P<0.05] and cell apoptosis, as well as reversing the structural injury of the lung under CIH condition. CIH leads to inflammatory stress, cell apoptosis and pathological changes within the lung, while HO-1 could inhibit inflammation and apoptosis, thereby reversing the pulmonary injury.

Effect of recombinant human granulocyte colony-stimulating factor on Nogo receptor expression in the brain tissues of neonatal rats after hypoxic-ischemic brain damage

Objective To observe the different effects of 2 doses recombinant human granulocyte colony-stimulating factors(rhG-CSF)on Nogo receptor(NgR)expression in the brain tissue of neonatal rats after hypoxic-ischemic brain damage(HIBD)at different times in order to reveal the neuroprotective effects of rhG-CSF. Methods Seven-day neonatal Sprague-Dawley(SD)rats were randomly divided into 4 groups by drawing method: sham operation group, model group, low-dose rhG-CSF group and high-dose rhG-CSF group, 24 rats in each group.Then each group was divided into 4 subgroups(6 rats in each subgroup)and all rats were exterminated at different times after HIBD(1 d, 3 d, 7 d and 14 d). In the low-dose rhG-CSF group and high-dose rhG-CSF group, the rats were given daily doses of rhG-CSF 50 μg/kg, 100 μg/kg respectively for 7 days by subcutaneous injection immediately after the molding(total 7 injections). In model group, rats received an injection of same amount of 9 g/L saline.In sham operation group, rats received no special treatment.Brain tissues of rats from each group were collected at different time points.The expressions of NgR protein and NgR mRNA in the left brain tissue were detected by immunohistochemistry and real-time fluorescent quantitative polymerase chain reaction(PCR). Results Immunohistochemistry: NgR proteins were constitutively expressed in the cerebral cortex in sham operation group at each time point; compared with sham operation group, the expressions of NgR in model group were increased markedly at each time point (135.67±16.63, 173.98±17.82, 234.00±14.70, 319.59±25.22), and the differences were statistically significant(all P<0.01); compared with model group, the expressions of NgR in the cerebral cortex in low-dose rhG-CSF group (134.35±8.89, 109.04±12.62, 75.99±13.39)and high-dose rhG-CSF group (81.38±12.25, 80.14±10.50, 72.58±13.66) on the 3rd, 7th, 14th day were reduced significantly(all P<0.01). Compared with low-dose rhG-CSF group, the protein expressions of NgR in the high-does rhG-CSF group were decreased faster, and had the marked difference on the 3rd, 7th day (P<0.05). Real-time fluorescent quantitative PCR: compared with the sham operation group, the expressions of NgR mRNA increased gradually in the cerebral cortex in the model group (1.34±0.24, 1.88±0.27, 2.88±0.84, 4.26±0.86), the differences in NgR mRNA expression were statistically significant at different times(all P<0.05); compared with model group, the expressions of NgR mRNA in low-dose rhG-CSF group on the 7th (1.08±0.30), 14th day (0.93±0.26) and high-dose rhG-CSF group on the 3rd(0.61±0.10), 7th(0.56±0.28), 14th day (0.47±0.12) were significantly different(all P<0.05). The expressions of low-dose group and high-dose group were reduced gradually.The NgR mRNA expression reduced more quickly in the high-dose group than in the low-dose rhG-CSF group and had substantial difference between two groups in 3 days (P<0.05). Conclusions The findings suggest that rhG-CSF intervention can reduce the expressions of NgR in the brain tissues of neonatal rats after HIBD, and low-dose rhG-CSF also has neuroprotective effect, but it could be weaker than high-dose rhG-CSF. Key words: Recombinant human granulocyte colony-stimulating factor; Hypoxic ischemic brain damage; Nogo receptor

Repeated DNA vaccination induced neonatal tolerance against Escherichia coli beta-galactosidase in immune-competent mice

Objectives: To induce neonatal immune tolerance in immune competent animals by repeated DNA vaccination. Materials and Methods: We used two groups of neonatal immune competent mice, C57BL/6, six in each. Mice in one study group received subcutaneous injection of 2 μg of endotoxin-free plasmid, pCBLacZ, at the posterior neck area. Concentration of the plasmid was 0.5 mg/mL. This plasmid encoded a potent immunogen, Escherichia coil beta-galactosidase. Mice in the other study group received intrarectal injection of same amount of pCBLacZ. All the animals received injection at the second day of birth and 5 consecutive injections of the same dose of pCBLacZ at an interval of 7 days. Seven days after the last shoot, the mice received an intramuscular injection of 50 μg of endotoxin-free pCBLacZ at a concentration of 2 mg/mL at the left anterior tibialis. We used 6 naive adult C57BL/6 as the control. These animals received an intramuscular injection of 50 μg of pCBLacZ at the left anterior tibialis at age of 42 days. Results: We examined the expression of beta-galactosidase in muscle fibers 6 days after the last intramuscular injection. The average numbers of fibers expressing beta-galactosidase was 168.2 in the mice receiving intrarectal immunization as compared with 0 in the mice receiving subcutaneous injection and 16.2 in their little mates. (p=0.001 by likelihood ratio test). There were two mice got 409 and 513 blue fibers respectively. Serum IgG against the beta-galactosidase was lower in the animals receiving intrarectal injection as compared with the mice in the other two groups by nonparametric Mann-Whitney test. Conclusions: Repeated DNA vaccination in the neonatal stage can induce immune tolerance against a potent immunogen in the immune competent animals. The ways of administration determine the success of tolerance induction.

A study on an examination method for the function of the palatine tonsil

As an aid for indication of tonsillectomy following simple method for examination of tonsil was devised. A 0.2cc, 0.8% methylene blue solution was injected into parenchyma of tonsil and fading time was measured. The shortest time was 3 minutes and longest over 90 minutes. After injection of same amount of 1% 2.6-dichlorphenolindophenol solution fading time was between 3 and 25 minutes. The fading time was short in cases of functional hypertrophy of tonsils, while longer in cases of severe chronic inflammation of tonsils. Thus, the fading was considered to be related to functional state of tonsils. Therefore, it was considered that fading reaction could be used for a criterion of indication of tonsillectomy, i. e. fading time of 30 minutes in case of methylene blue and that of 10 minutes in case of 2.6-dichlorphenolindophenol were taken for indication of tonsillectomy.The fading reaction was thought to be mainly due to reduction and partially to res or ption and phagocytosis of dyes. It was found that mainly tissue vitamin C and phartially glutathion and succinic dehydrogenase participate in reduction of dyes.