AIM:To study the expression of glycine receptorα1 subunit in neonatal rat myocardial cells and to investigate the effect of lipopolysaccharide (LPS), hypoxia/reoxygenation, isoproterenol (ISO) and high concentration of glucose (HG) on the expression of glycine receptorα1 subunit in the neonatal rat myocardial cells.METHODS:Neonatal rat myocardial cells were cultured in vitro.The expression of glycine receptorα1 subunit was detected by Western blotting. The neonatal rat myocardial cells were treated with LPS (20 mg/L), ISO (100 μmol/L) or high concentration of glucose (25 mmol/L) for 24 h, or were exposed to hypoxia for 3 h followed by reoxygenation for 3 h.Subsequently, the cell viabil-ity was measured by CCK-8 assay, and the expression of glycine receptorα1 subunit was determined by Western blotting. RESULTS:The expression of glycine receptor α1 subunit in the neonatal rat myocardial cells was positively detectable by Western blotting.Compared with control group, no significant difference of the cell viability ( P>0.05) in LPS group, ISO group, hypoxia/reoxygenation group and HG group was observed.The expression of glycine receptor α1 subunit was in-creased (P<0.01) in LPS group, ISO group and hypoxia/reoxygenatio group, but decreased (P<0.01) in HG group. CONCLUSION:Glycine receptorα1 subunit exists in the neonatal rat myocardial cells.A certain concentration of LPS or ISO, or hypoxia/reoxygenation for a certain period upregulate the expression of glycine receptorα1 subunit, but HG down-regulates the expression of glycine receptor α1 subunit in cultured neonatal rat myocardial cells.

AIM:To study the protection of Glycyl-L-Glutamine(Gly-Gln) against myocardial ischemia/reperfusion(I/R) injury in the isolated rat heart.METHODS:A model of myocardial ischemia-reperfusion injury was established with a Langendorff apparatus.Thirty male SD rats were randomly divided into four groups:control group,Gly-Gln group,I/R group and I/R+Gly-Gln group.Both I/R and I/R+Gly-Gln group were pre-perfused for 30 min,followed by 20 min ischemia and 40 min reperfusion.During reperfusion I/R+Gly-Gln group was perfused with Gly-Gln perfusate.Control group was kept perfused for 90 min.Gly-Gln group Gly-Gln perfusate was also kept perfused for 90 min.The left ventricular end-diastolic pressure(LVEDP),left ventricular developed pressure(LVDP),?dp/dtmax,heart rate(HR),monophasic action potentials(MAP) was measured during perfusion.The coronary effluent fluid was collected at different certain times.The activities of lactic dehydrogenase(LDH) and creatine kinase(CK) were determined.RESULTS:The isolated rat heart function decreased severely after 20 min ischemia and 40 min reperfusion(I/R):the LVEDP increased and the LVDP,?dp/dtmax decreased.But the LVEDP decreased and the LVDP,?dp/dtmax increased in I/R+Gly-Gln group compared with I/R group.Moreover,the activities of LDH and CK in the coronary effluent fluid decreased remarkably in I/R+Gly-Gln group compared with I/R group.CONCLUSION:Gly-Gln can play a protective role against myocardial I/R injury in isolated rat hearts via maintaining the left ventricular function and decreasing the release of LDH and CK.

AIM: To study the effect of food intake on weight, memory, staying balance and power, and some biochemical indexes in mice. METHODS: In accordance with the average food intake everyday, the animals were divided into five groups: group A took the average food intake fully, group B took 75% of the average food intake, group C took 50% of the average food intake, group D took 25% of the average food intake, and group E did not take any food at all. The weights, memory, staying balance and power were recorded every three days, the biochemical index was recorded on the 10th day. RESULTS: On the 3rd day, the weight and staying balance and power of mice in group E decreased. On the 6th and 9th day, the weight of mice in group ABC increased. Compared with group B and C, the memory group A and D decreased. On the 10th day, the blood glucose concentratoin in of group D decreased, total cholesterol and triglyceride also decreased with the reduction of food intake. CONCLUSION: A food intake of 75%-50% in all helpes to keep a good body status and memory, decreases total cholesterol and triglyceride in blood.

AIM: To investigate the protective effects of berberine against liver injury induced by lipopolysaccharide in mice and the mechanisms underlying its protective effect.METHODS: The male mice were divided randomly into control,berberine group,LPS group and berberine treatment group.Mice were administered intragastrically with distilled water(0.01 mL/g) or(5 g/L) neutral sulfate berberine(0.01 mL/g) once a day for 5 days and injected intraperitoneally with normal saline or LPS(0.02(mL/g),28 mg/kg)at 1 h after gavage on day 5.Blood was collected for determining alanine aminotransferase(ALT) and aspartate aminotransferase(AST) activities,the content of tumor necrosis factors-?(TNF-?) at 10 h and 2 h after LPS or normal saline injection,respectively.Furthermore,the liver tissue was processed,and histological changes and ultrastructure in liver were observed with light and electron microscopy,malondialdehyde(MDA) content and superoxide dismutase(SOD) activity in liver were also detected.RESULTS: Both ALT and AST activities in serum in LPS group were higher than those in control and berberine treatment group.LPS increased the serum TNF-? content at 2 h after injection,which was reversed by berberine pretreatment.The histological examination showed that LPS caused severe hepatic cell edema,degeneration,apoptosis and even necrosis,and ultrastructure observation demonstrated that LPS induced mitochondrial swelling,condensation and margination of chromatin,irregular nuclear envelope in hepatocytes.The above pathological changes produced by LPS were attenuated by berberine pretreatment.Moreover,MDA contents in liver tissue were higher in LPS group than control and berberine treatment group,but there were no significant difference in SOD activity between berberine treatment and LPS group.CONCLUSION: Berberine has a protective effect on LPS-induced liver injury in mice,the mechanisms may be related to its decreasing the production of TNF-?,inhibiting lipid peroxidation and protecting mitochondria.

AIM:To explore the preliminary mechanism of senegenin ( Sen) on inhibiting hypoxia/reoxygenation ( H/R)-induced apoptosis of primary cortical neurons .METHODS:The cultured cortical neurons were randomly divided in-to normal group (control group), model group (H/R group), Sen+H/R group and Sen group.Flow cytometry was used to evaluate the effect of Sen on H/R-induced cell apoptosis .The protein levels of JNK , p-JNK, c-Jun, p-c-Jun, Bcl-2 and Bax were assessed by Western blotting .RESULTS:The apoptotic rate in H/R group was obviously higher than that in control group (P<0.05), while the apoptotic rate in Sen +H/R group was obviously lower than that in H/R group (P<0.05), suggesting that the model of apoptosis was established successfully .The results of Western blotting showed that Sen increased the expression of JNK and c-Jun, inhibited the phosphorylation of JNK and c-Jun (P<0.05), increased the protein level of Bcl-2 and inhibited the protein level of Bax in H/R treated primary cortical neurons (P<0.05).CONCLUSION:Sen has a protective effect against H/R-induced neuronal apoptosis by increasing the expression of JNK and c-Jun, inhibiting the phosphorylation of JNK and c-Jun, increasing the protein level of Bcl-2 and decreasing the protein level of Bax .

AIM: To observe the protective effect of non-wounded ischemic preconditioning on ischemic/reperfusion injury in isolated rat hearts. METHODS: 25 male SD rats, weighting (250?30) g, were randomly divided into three groups: control group (C, n= 8), anoxia/reoxygenation group (A, n= 8) and non-wounded legs ischemic preconditioning group (N-WIP, n= 9).Hearts were isolated from rats and perfused on a Langendorff apparatus with a normal Krebs-Henseleit buffer (saturation 95% O 2+5% CO 2) at a constant pressure (8.33 kPa) and temperature (37 ℃) in C group ; Following 15 min equilibration, hearts were subjected to 15 min of global ischemia and 15 min reperfusion (37℃) in A group ; Rats were subjected to non-wounded leg repeated-brief ischemic preconditioning, and then treated in procedure similar to A group in N-WIP group.The activities of superoxide dismutase (SOD) and Ca 2+ -Mg 2+ -ATPase, malondialdehyde (MDA) content of efflux from coronary vessel and myocardium, myocardium monophasic action potential and contractile force were measured before ischemia, 15 minutes after ischemia and 5, 15 minutes after reperfusion. RESULTS: Compared with A group, non-wounded legs ischemic preconditioning reduced the incidence of reperfusion arrhythmias ( P

AIM: To observe the effects of berberine (Ber) on enterocyte apoptosis in septic mice and its pos-sible mechanism.METHODS: Male C57BL/6 mice (8 ~10 weeks old) were randomly divided into sham group, cecal ligation and puncture (CLP) group, CLP +Ber group and sham +Ber group.The mice in CLP group underwent CLP ope-ration, and the mice in sham groups suffered a similar operation except the ligation and puncture.After the sham or CLP operation, the mice were administered intragastrically with distilled water or berberine (50 mg/kg) within 2 h.After 20 h, the mice were killed with excess pentobarbital sodium and the ileum tissues were removed.The histological changes of the intestine were observed and the enterocyte apoptosis was examined by determining the protein level of cleaved caspase-3. Furthermore, mitochondrial Bax, cytoplasm cytochrome C (Cyt C) and the total proteins of Bcl-2, Fas, FasL and Fas-as-sociated protein with death domain (FADD) were examined by Western blot.The mRNA expression of tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH) was measured by real-time PCR.RESULTS: The extensive ileum injuries, including remarkably increased leukocytes and necrosis of intestinal villus were observed 20 h after CLP.In CLP group, the protein levels of cleaved caspase-3, cytoplasm Cyt C, as well as Fas, FasL were significantly increased, but the Bcl-2 level was decreased.Bax translocation into mitochondria was promoted.However, FADD was not changed significantly.The mRNA expression of TH and DBH was also increased sharply in CLP group.On the contrary, treatment with berberine made a considerable alleviating alteration in the ileum of the septic mice.CONCLUSION: Treatment with berberine pro-vides protective effects on intestinal injury in septic mice by reducing enterocyte apoptosis, and its possible mechanism may be involved in the inhibition of the endogenous and exogenous apoptosis pathways.

AIM: To observe the influence of glycine on intracellular free calcium, the concentration of tumor necrosis factor-? and the survival rate of myocardial cells during hypoxia/reoxygenation (H/R). METHODS: The simulated model of myocardial ischemia-reperfusion with the primary cultured cardiomyocytes of neonatal rats was established, and the cultured cardiomyocytes were divided into seven groups, control group, hypoxia/reoxygenation group, glycine (0.5 mmol/L) plus hypoxia/reoxygenation group, glycine (1.0 mmol/L) plus hypoxia/reoxygenation group, glycine (2.0 mmol/L) plus hypoxia/reoxygenation group, glycine (4.0 mmol/L) plus hypoxia/reoxygenation group, 4.0 mmol/L glycine group. RESULTS: Within certain concentration (0.5-2.0 mmol/L), the glycine could inhibit the calcium overload resulting from hypoxia/reoxygenation injury in cells in a dose-dependent manner with the optimal inhibitory effect at 2.0 mmol/L. Glycine inhibited the secretion of tumor necrosis factor-? from myocardial cells and increased the survival rate of myocardial cells. CONCLUSION: Glycine has a protective effect on hypoxia/reoxygenation myocardial cells, which may be related to inhibiting calcium overload and decreasing the production of tumor necrosis factor-?.

AIM: To investigate the differences of Alzheimer's disease(AD)-related parameters in the SAM-P/8, the SAM-R/1 and the Kunming mice.METHODS: The changes of ethology, neurobiochemistry (true choline esterase, TchE), ultrastructure and gene expression(gene chips) were determined in mice of three groups: SAM-P/8 mice (n=14), SAM-R/1 mice (n=14) and Kunming mice (n=14), which were 6 months old[weight(20?5)g].RESULTS: The SAM-P/8 mice had the inabilities of learning and memory compared with the SAM-R/1 mice and the Kunming mice (P

The primary action of corticotropin releasing hormone (CRH) is stimulation of the synthesis and release of adrenocorticotropic hormone and β-endorphin from the pituitary in response to stress. In addition, a number of studies indicate that CRH exerts other physiological actions within the central nervous system which are independent of the pituitary. These include increased body temperature and thermogenesis. However, the intracellular mechanism responsible for pyrogenic action of CRH is still unclear. The purpose of these studies was to determine whether or not cAMP was involved in the pyrogenic action of CRH in the rat. Intracerebroventricular (icv) microinjection of CRH (2.5 μg, 5.0 μg, 10 μg) caused increases in colonic temperature and hypothalamus cAMP level in conscious rats. The pyrogenic effects of CRH were abolished or markedly inhibited by prior injection (icv) of an adenylate cyclase inhibitor, 2，，3，-dideoxyadenosine (DDA, 30 μg) or an inhibitor of cAMP-dependent protein kinase, adenosine-3，，5，-(cyclic) monophosphorothionate (Rp-cAMPs, 15 μg). This is the first report demonstrating the pyrogenic effcet of centrally administration of CRH on the rat via the cAMP-mediated protein kinase signal transduction pathway.