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Objective To investigate the potential effect and mechanism of curcumin in inhibiting synaptic injury in the cortex of rats with cerebral ischemia-reperfusion. Methods Sprague-Dawley rats were divided into sham-operated group, model group, low-dose curcumin (50 mg/kg) group, and high-dose curcumin (100 mg/kg) group. A model of middle cerebral artery occlusion for 2 hours and reperfusion for 24 hours was constructed, and curcumin was administered. Based on the neurological function score, the effects of curcumin on cerebral infarct volume, synaptic ultrastructure changes, inflammatory cell infiltration, and the expression of NLRP3, Caspase-1, Synapsin1, and CAMKⅡ were observed after the end of the animal treatment. Results The neurological function scores were 0, 3.25±0.43, 2.50±0.50, and 1.50±0.50 for the sham-operated group, model group, low-dose curcumin group, and high-dose curcumin group, respectively. The percentage of cerebral infarct volume was 0, (38.89±2.21)%, (33.48±1.77)%, and (23.69±2.19)%, respectively. Compared with the sham operation group, the model group had severe synaptic ultrastructure damage, extensive inflammatory cell infiltration, significantly increased expression of Caspase-1 and NLRP3 (P < 0.5), and significantly decreased expression of Synapsin1 and CAMKⅡ (P < 0.5). Curcumin treatment significantly inhibited synaptic damage, reduced inflammatory cell infiltration, decreased the expression of Caspase-1 and NLRP3 (P < 0.5), and increased the expression of Synapsin1 and CAMKII (P < 0.5), when compared with the model group. Conclusion Ischemia-reperfusion-mediated synaptic injury in rat brain triggers an inflammatory response in cortical nerve cells, and curcumin alleviates synaptic damage and reduces brain injury by inhibiting inflammatory factor levels.
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OBJECTIVE@#To investigate the expression of Ca2+/calmodulin-dependent protein kinase II (CaMK Ⅱ) in pancreatic tissues of mice with severe acute pancreatitis (SAP) and explore the protective effect of KN93, a CaMK Ⅱ inhibitor, against pancreatic injury in SAP and the possible mechanism.@*METHODS@#Thirty-six healthy male C57 mice were randomly divided into sham operation group, SAP group, KN93 group and SAP + KN93 group (n=9). Serum and pancreatic tissue samples were collected 24 h after modeling. The pathological changes in the pancreatic tissues were observed using HE staining. Serum lipase and amylase activities and the levels of inflammatory factors were detected using ELISA. Western blotting was used to detect the expressions of CaMK Ⅱ, p-CaMK Ⅱ, p-NF-κB, MAPK and p-MAPK in mouse pancreas.@*RESULTS@#Compared with those in sham operation group, the expressions of p-CaMK Ⅱ, p-NF-κB and p-MAPK were significantly increased in SAP group (P < 0.05). KN93 treatment obviously alleviated pathological injuries of the pancreas in SAP mice, and significantly lowered serum levels of lipase, amylase and inflammatory factors (TNF-α and IL-6) and phosphorylation levels of NF-κB, ERK and MAPK proteins (P < 0.05).@*CONCLUSION@#The activity of CaMK Ⅱ is significantly increased in the pancreatic tissue of SAP mice. KN93 can alleviate pancreatic injury and inflammation in SAP mice possibly through the ERK/MAPK signaling pathway.
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Animals , Male , Mice , Acute Disease , Inflammation/metabolism , NF-kappa B/metabolism , Pancreas/pathology , Pancreatitis/pathologyABSTRACT
OBJECTIVE@#To observe the effect of acupoint thread-embedding on tight junction of intestinal mucosal epithelial barrier in rats with ulcerative colitis (UC) under the state of "deficiency and stasis", and to explore its mechanism.@*METHODS@#Sixty male SD rats were randomly divided into a control group (@*RESULTS@#Compared with the control group, in the model group the body weight was decreased (@*CONCLUSION@#The thread-embedding could repair the tight junction of intestinal mucosa epithelium and reduce the permeability of intestinal mucosa epithelium, which may be related to the decrease of the expression of CaMKⅡ, MLCK and other protein kinases.
Subject(s)
Animals , Male , Rats , Acupuncture Points , Colitis, Ulcerative/therapy , Epithelium , Intestinal Mucosa , Rats, Sprague-Dawley , Tight JunctionsABSTRACT
OBJECTIVE：To study th e effects of dexmedetomidine on ventricular arrhythmia in myocardial hypertrophy model rabbits and the expression of calcium ion /calmodulin-dependent protein kinase Ⅱ（CaMKⅡ）in myocardial tissue of rabbits. METHODS： The rabbits were randomly divided into sham operation group ， model group ， dexmedetomidine low-dose ， medium-dose and high-dose groups （10，25，50 μ g/kg），CaMK Ⅱ inhibitor KN- 93 group （10 mg/kg），high-dose of dexmedetomidine+KN-93 group（50 μg/kg+10 mg/kg），with 10 rabbits in each group. Except for the sham operation group ，other groups received abdominal aortic coarctation to induce myocardial hypertrophy model. After surgery ，administration groups were given relevant dose of dexmedetomidine or/and intraperitoneal injection of KN- 93；sham operation group and model group were given constant volume of normal saline intravenously ，once every other day ，for consecutive 8 weeks. After last medication ， programmed stimulation was used to induce ventricular arrhythmia. The induction rate of early posterior depolarization （EAD）and tip torsion type ventricular tachycardia （Tdp）were recorded. Left ventricular ejection fraction （LVEF）and left ventricular shortener fraction（FS）were measured. QT interval ，transventricular wall repolarization dispersion （TDR）and transmembrane 90％ action potential duration （APD90）of endocardial and epicardial cardiomyocytes in wedge-shaped myocardium were recorded. The ratio of heart weight to body weight （HW/BW）and the thickness of left ventricular wall （LVT）were measured and calculated. The cross-sectional area of cardiomyocytes ，mRNA expression of ANP and BNP as well as protein expression of CaMK Ⅱ and p-CaMK Ⅱ in myocardial tissue was measured. RESULTS ：Compared with sham operation group ，the induction rate of EAD and Tdp ，HW/BM， LVT，mRNA expression of ANP and BNP and protein relative expression of CaMK Ⅱ and p-CaMK Ⅱ in cardiac tissue were all increased significantly ，while LVEF and FS were decreased significantly ；QT interval ，APD90 of endocardial and epicardial cardiomyocytes were all prolonged significantly ；TDR was increased significantly ，while cross-sectional area of cardiomyocytes was increased significantly in model group （P＜0.05）. Compared with model group ，induction rate of EAD and Tdp ，HW/BW （except for dexmedetomidine low-dose group ），LVT（except for dexmedetomidine low-dose group ），mRNA relative expression of ANP（except for dexmedetomidine low-dose group ）and BNP （except for dexmedetomidine low-dose group ）as well as protein relative expression of CaMK Ⅱ and p-CaMK Ⅱ were all decreased significantly in administration groups ；the levels of LVEF （except for dexmedetomidine low-dose group ） and FS （except for dexmedetomidine low-dose group ） were all increased significantly； QT interval ，APD90 of endocardial and epicardial cardiomyocytes were shortened significantly ； TDR and cross-sectional area of cardiomyocytes （except for dexmedetomidine low-dose group ）were decreased significantly （P＜0.05）；the improvement effects of dexmedetomidine high-dose group were significantly better than those of dexmedetomidine low-dose and medium-dose groups （P＜0.05）. Compared with dexmedetomidine high-dose group and KN- 93 group，the improvement of above indexes were all more significant in high-dose of dexmedetomidine+KN- 93 group（P＜0.05）. CONCLUSIONS ：Dexmedetomidine can reduce the induction rate of ventricular arrhythmia and improve myocardial hypertrophy in myocardial hypertrophy model rabbits，the mechanism of which may be associated with down-regulation of CaMK Ⅱ expression.
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ObjectiveIvabradine reduces heart rate by inhibiting If current of cardiomyocyte and is used clinically to treat stable angina pectoris and myocardial ischemia. However, the mechanism of positive inotropic effect by Ivabradine is still not well understood. This study aims to investigate the Ivabradine's positive inotropic effect both in vivo and in vitro and the underlying mechanism involved.Methods①A Millar catheter with double-pressure was inserted into the right carotid artery of general anesthesia rats. The pressure-volume of left ventricle, HR (heart rate) and aortic pressure were recorded as a blank group (n=7). The effect of Ivabradine (1 mg/kg) administrated via left external jugular vein was recorded as a drug treated group (n=7). The cardiac output, left ventricular and aortic pressure of the rats in the blank group A and the administration group A were compared, and the results were used to analyze the Ivabradine's inotropic effectin vivo.②Langendorff setup was used to analyze the left ventricular pressure of the isolated heart. The normal perfusion solution was used as the blank group (n=6), while the Ivabradine (10 μmol/L) perfusion was used as the treated group (n=6). In addition, the treatment of H89 (200 nmol/L) (a PKA inhibitor) was recorded as the blank group (n=6) and the combined use of H89 (200 nmol/L) and Ivabradine (10 μmol/L) was recorded as drug treated group (n=6). Following the above protocol, KN-93 (500 nmol/L) (a CaMKII inhibitor) or CA (10 nmol/L) (a protein phosphatase 1 and 2A inhibitor) was used to analyze the inhibitory effect on inotropic effect of Ivabradine (n=6 for each group). ③The field stimulation induced Ca2+ transient from cardiomyocyte was used to investigate the mechanism underlying the positive inotropic effect of Ivabradine (10 μmol/L).The perfusion orders and concentrations of Ivabradine or/and H89, KN-93 and CA were the same as that in isolated rat heart experiment (n= 6 for each group).Results① Ivabradine (1 mg/kg) significantly increased the left ventricular develop pressure (from 102.43±11.06 in blank group to 109.86±11.65 mmHg in ivabradine treated group, P<0.01, n=7) and cardiac output (from 33.72±1.96 in blank group to 36.27±2.22 mL/min in ivabradine treated group, P<0.01, n=7). It reduced the heart rate (from 348.56±10.02 in blank group to 324.17±11.33 beats/min in ivabradine treated group, P<0.01, n=7) and increased the systolic blood pressure (from 99.74±8.67 in blank group to 108.57±9.24 mmHg in Ivabradine treated group, P<0.01, n=7) without significant change in diastolic blood pressure. ② Ivabradine (1, 10 μmol/L) significantly increased the left ventricular developed pressure (LVDP) (P<0.05, n=6). The positive inotropic effect of Ivabradine was blocked by CaMKⅡ inhibitor of KN-93. ③ Ivabradine (10 μmol/L) significantly increased the amplitude of SR Ca2+ transient (P<0.01,n=6). The enhanced amplitude of Ca2+ transient was blocked by CaMKⅡ inhibitor of KN-93.ConclusionIvabradine shows a positive inotropic effect in rat hearts both in vivo and in vitro and its underlying mechanism involved the action which was mediated by CaMKⅡ.
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Objective::To study the effect of Hei Xiaoyaosan on the expression of calcium calmodulin-dependent protein kinase Ⅱ alpha(CaMKⅡα) and its phosphorylation in hippocampus and cortex of mice with Alzheimer's disease. Method::After weighing, 30 APP/PSI transgenic male mice were divided into model group, donepezil hydrochloride group and Hei Xiaoyaosan group according to random principle and 10 in each group.At the same age, wild-type C57BL/6 10 mice of the same species were treated as blank group. Donepezil hydrochloride group (6 g·kg-1) and Hei Xiaoyaosan group (3.25 mg·kg-1) were administered for 90 days, then the behavior of all the mice were detected by Morris water maze, the expression of CaMKⅡα, p-CaMKⅡα proteins in hippocampus and cortex by immunohistochemical technique and Western blot. Result::After intervention 3 months, compared with blank group, the average escaping latency periods prolonged significantly and the number of cross-platform and effective areas were decreased distinctly in model group mice(P<0.01), CaMKⅡα protein relative expression decreased significantly(P<0.01), p-CaMKⅡα protein relative expression increased significantly(P<0.01). Compared with the model group, the escape latency of donepezil hydrochloride and Hei Xiaoyaosan group were significantly shortened, and the number of crossing platforms and effective areas was significantly increased (P<0.05, P<0.01), the expression of CaMKⅡα protein in the hippocampus and cortex of drug groups was significantly increased (P<0.01), p-CaMKⅡα protein in the hippocampus and cortex of drug groups was significantly decreased (P<0.05, P<0.01). Conclusion::Hei Xiaoyaosan can improve the learning and memory ability of AD mice by regulating the expression of CaMKⅡα and its phosphorylation, which are key proteins involved in the mechanism of cell memory formation in different brain regions of AD mice.
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Alzheimer's disease（AD） is an incipient aging neurodegenerative disease， which increases rapidly along with the development trend of social aging and seriously threatens the health of the people. In the absence of effective preventive measures， it will have an enormous impact on the socio-economic and healthcare system. The study found that abnormal cell signal transduction is a key link in many diseases. Cell signal transduction theory has been widely used to clarify the essence of traditional Chinese medicine visceral image and the mechanism of traditional Chinese medicine. 'Correlation of Liver and Kidney' is one of the core plates of the theory of 'Correlation of Five Organs'， which is suitable for explaining the pathogenesis of complex diseases and the correlation of multiple syndromes， and guiding the prescription of clinical syndrome. Hei Xiaoyaosan， as the first choice compound for the prevention and treatment of AD based on the theory of "Correlation of Liver and Kidney' in our team， can play the effects of prevention and treatment by soothing liver and nourishing blood， strengthening spleen and tonifying kidney， and promoting brain collaterals and dredging viscerab spirit. Based on the theory of 'Correlation of Liver and Kidney'， this paper expounds the pathogenesis of AD from the perspective of traditional Chinese medicine， and puts forward the methods and ideas of the preventing and treating of AD from Ca2+-calcium/calmodulin dependent protein （CaM）/calcium/calmodulin dependent protein kinaseⅡ（CaMKⅡ）-cyclic adenosine phosphate reactive element binding protein （CREB） cell signal transduction pathway by consulting literatures and previous studies.
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Objective: To observe the effects of puerarin on the expressions of CaM, CaMKⅡ, BDNF and Akt in vascular dementia cell models induced by oxygen and glucose deprivation (OGD). Methods: The passaged well-differentiated PC12 cells were randomly divided into control group, model group, and low-dose, medium-dose and high-dose intervention groups. Vascular dementia cell model was established by OGD. Suitable OGD time and concentration of puererin were obtained from the cell viability measured by MTT assay. The release of LDH was measured to assess the extent of cell damage and identify cell models. The expressions of CaM, CaMKⅡ, MECP2, BDNF and Akt were detected by Western blot. Results: PC12 cells with OGD prolonged viability decreased in a time-dependent manner, with increased concentrations of puerarin increased in a concentration-dependent manner. Effective intervention of puerarin was 0.1-10 μmol/L and optimal time of OGD was 6 h. Compared with control group, the release of LDH in model group was significantly increased (P0.05). Puerarin could down-regulate the level of CaM protein, increase the expressions of MECP2 and BDNF and the phosphorylation of CaMKⅡ, and also increase the phosphorylation of Akt in addition to the low-dose group (P<0.05). Conclusion: The neuroprotective effect of puerarin may be related to the increase of the autophosphorylation of CaMKⅡ mediated by Ca2+-CaM complex, induce the phosphorylation of MECP2, up-regulate the expression of BDNF and activate the PI3K-Akt pathway to inhibit the expression of apoptotic genes and proteins.
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Objective: To study the protective effect of Huayu Qutan decoction on vascular dementia (VD) gerbils and to explore whether its mechanism is related to Calcium ion-calmodulin-dependent protein kinase Ⅱ (CaMKⅡ)/cyclic adenosine effect element binding protein (CREB)/brain-derived neurotrophic factor (BDNF) signaling pathway. Method: Forty healthy gerbils were randomly divided into sham operation group, model group, low, medium and high dose groups (5.35, 10.7, 21.4 g·kg-1) of removing blood stasis and expelling phlegm. Eight gerbils in each group were divided into model group and removing blood stasis and expelling phlegm group. Gerbils were given corresponding drugs twice a day after operation. Water maze experiment was conducted 21 days later to investigate the spatial learning and memory ability of gerbils. The expression of p-CaMKⅡ/CaMKⅡ, p-CREB/CREB and BDNF in the hippocampus of gerbils were detected by Western blot and immunohistochemistry. Result: Compared with sham operation group, the incubation period and the number of platform trips of gerbil in the model group were significantly reduced, p-CaMKⅡ/CaMKⅡ, p-CREB/CREB, and BDNF protein expression were significantly reduced (PPPConclusion: Huayu Qutan decoction improves the learning and memory abilities of gerbils with vascular dementia, and its mechanism may be related to the activation of CaMKⅡ/CREB/BDNF signaling pathway.
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OBJECTIVE To investigate the protective effect of Codonopsis Pilosula Polysaccharide (CPPS) on improving of the memory consolidation disorder induced by Cycloheximide and its possible mechanisms in mice. METHODS The mice was divided into five groups, as normal control group, cycloheximid model group, piracetam positive control group, CPPS 300 mg · kg- 1 group, and CPPS 150 mg·kg-1 group. The mice respectively were given saline, piracetam, and CPPS for 15 d. The memory consolidation disorder model in mice was established by ip. Cyclohexylamine, and orally administered CPPS(300 mg·kg-1 or 150 mg·kg-1) every day. Then experimental groups were subjected Morris Water Maze test. Western blotting analysis were used to analysis the expression of CaMKⅡ/CREB signaling pathways. RESULTS Morris water maze experiment showed that cyclohexylamine can cause memory consolidation disorder(P<0.01), and giving piracetam and CPPS (300 mg · kg- 1) can improve spatial memory impairment in mice(P<0.05, P<0.01). Western blotting experiment results show that compared with normal control group, CaMKⅡ and CREB contents of brain in model group mice had significant decreased(P<0.001); Compared with model group, CaMK Ⅱ and CREB contents of brain tissue in piracetam and CPPS groups increased significantly(P<0.05,P<0.01,P<0.001). CONCLUSION Cyclo?heximide can induce the memory consolidation disorder, and its effect in mice related to CaMK/CREB signaling pathways. CPPS can improved this memory disorder by influence CaMKⅡ/CREB signaling pathways.
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Objective To investigate the effects of epidural ropivacaine block combined with propofol intravenous anesthesia on CaMKⅡ and ERK1/2 total protein (T-CaMKⅡ and T-ERK1/2) and phosphorylation(p-CaMKⅡ and p-ERK1/2) levels in the hippocampus and cortex of rats.Methods Rats were randomly assigned to three groups: group P(control,propofol intravenous anesthesia),group PS(propofol and epidural normal saline) and group PR(propofol and epidural 0.5% ropivacaine).Anesthesia were performed in 72 h after epidural catheter placement.The rats in group PR received 70 μL of 0.5% ropivacaine to achieve epidural block.1% propofol was infused through rats caudal vein.Propofol dosage for anesthesia induction was 12 mg/kg,for anesthesia maintenance was 40 mg/(kg·h).Before the rats were decapitated,the depth of anaesthesia was assessed as either light anesthesia or deep anesthesia by checking of pinch withdrawalreflex,eyelid reflex and spontaneous rapid whisking of the vibrissae after propofol continuous infusion for 1 h.T-CaMKⅡ/T-ERK1/2 and p-CaMKⅡ/p-ERK1/2 in hippocampus and frontal cortex were examined by Western blot.Results 7 rats were assessed as light anesthesia and one rat as deep anesthesia in group P;6 rats were assessed as light anesthesia and 2 rats as deep anesthesia in group PS;in group PR,1 rat was assessed as light anesthesia and 7 rats as deep anesthesia.Significant differences were seen among three groups (P<0.05).In hippocampus of rats,p-CaMKⅡ(Thr286)43.7%±8.8% and p-ERK1/2 32.4%±7.9% in group PR were significantly lower than those in group P (100%,P<0.05).Conclusions Epidural ropivacaine block may strengthen the depth of anesthesia achieved with propofol intravenous anesthesia.The decrease of p-CaMKⅡ(Thr286) and p-ERK1/2 in hippocampus of rats may explain the effects of epidural block.
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Objective To investigate the effect of CaMK Ⅱ expression on apoptosis of rat hepatocytes BRL-3A.Methods Rat BRL-3A cells were stable passage were cultured.The CaMK Ⅱ γ protein (LV-CaMK Ⅱ γ group) and CaMK Ⅱ γshRNA (shRNA group) lentiviral expression systems were constructed.The corresponding blank vectors (LV-NC group and shRNA-NC group) and normal saline (CON group) were perfused into the control groups.The expression levels of CaMK Ⅱ,Cyt C and MF proteins were detected by Western blotting,and the apoptosis rate of BRL-3A cells was measured by Tunel method.Results The protein expression of CaMK Ⅱ,Cyt C and AIF in LV-CaMK Ⅱ γ group was significantly higher than that in CON group (P＜0.05).The protein expression of CaMK Ⅱ,Cyt C and AIF in shRNA group was significantly lower than that in CON group (P＜ 0.05).There was no significant difference among CON group,LV-NC group and shRNA-NC group (P＞0.05).At the same time point,the apoptosis rate of hepatocytes in LV-CaMK Ⅱ γ group was significantly higher than that in CON group (P＜0.05).At the same time point,the apoptosis rate of hepatocytes in shRNA group was significantly higher than in CON group (P＜0.05).There was no significant difference in the apoptosis of hepatocytes among CON group,LV-NC group and shRNA-NC group (P＞0.05).Conclusion The specific CaMK Ⅱ signaling pathway can inhibit the apoptosis of BRL-3A cells,while the enhanced CaMK Ⅱ signaling pathway promotes the apoptosis of BRL-3A cells.
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Objective To investigate the role of CaM/CaMK-Ⅱ signaling pathways in inflammatory pain in mice.Methods Sixty male C57BL6 mice,weighing 25-27 g,were randomly divided into 3 groups (n =20):control group (group C),complete freunds adjuvant (CFA) group (group F) and KN-93+CFA group (group KF).Saline 50 μl were injected into the right side of the claw in group C.CFA 50 μl were injected into the right claw foot for the preparation of inflammatory pain models in group F.KN-93 45 nmol was injected i.c.v.30 min before CFA injection in group KF.The thermal withdrawal latency (TWL) were measured 30 min before injection,1 h and 4 h after injection.The protein expressions of CaMK-Ⅱ,c-fos and CREB in the spinal cord were measured at above time by Western blot.Results Compared with group C,TWL were lower in groups F and KF 1 h and 4 h after injection (P＜0.05).Compared with groups F,TWL in group KF were higher 1 h and 4 h after injection (P＜0.05).Compared with group C,the protein expressions of p-CaMK-Ⅱ,p-CREB,e-fos and mRNA expression of CaMK-Ⅱ,CREB,c-fos were higher in group F and KF 1 h and 4 h after injection (P＜0.05).Compared with group F,the protein expression of p-CaMK-Ⅱ,p-CREB,c-fos and mRNA expressions of CaMK-Ⅱ,CREB,c-fos in group KF were lower 1 h and 4 h after injection (P＜0.05).Conclusion CaM/CaMK-Ⅱ signaling pathways involved in inflammatory pain in mice.
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Aim ToinvestigatetheeffectsofCa2+/calmodulin-dependent protein kinase Ⅱ inhibitor KN-93 on calcium overload-induced heart injury.Methods Thirty-twoisolatedratheartswererandomlydivided into the control group,KN-93 control group,calcium paradox group,and calcium paradox with KN-93 treat-ment group.Left ventricular pressure were recorded, and the heart function was evaluated by the left ventric-ular end-diastolic pressure (LVEDP ) and developed pressure (LVDP).Coronary flow (CF)were collect-ed,and lactate dehydrogenase (LDH)content was de-termined.Triphenyltetrazolium chloride staining was usedtomeasuretheinfarctsize.Results Compared with the control group,KN-93 at 2. 5 μmol·L-1 had no effects on coronary flow,cardiac performance and cell death at the end of perfusion in normal rats (P>0. 05 );The hearts of calcium paradox exhibited a de-crease in LVDP and CF,meanwhile an increase in LV-EDP,LDH,and infarct size of 18 ±7. 2% (P <0. 01).2. 5 μmol·L-1 KN-93 further increased the levels of LVEDP,LDH and infarct size (P<0. 01)in Ca2+paradoxical hearts,while it provoked the decline intheCFandLVDP(P<0.01).Conclusion The data demonstrates that KN-93 aggravates heart injury in calcium paradox,it also suggests that CaMKⅡ is in-volved in the Ca2+overload-induced heart injury.
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Objective To observe the effects of acupuncture on synaptic transmission signal molecules in rats with vascular dementia (VD), such as PKC, CaMKⅡ and NR2B, and discuss the molecular mechanism of acupuncture treatment for VD.Methods The multi-infarct dementia model was established by injection of emboli into the internal carotid artery. Experimental rats were randomly divided into normal group, model group, acupuncture group and non-acupoint group. For acupuncture group, acupuncture needles were penetrated into bilateral Zusanli. Non-acupoint group was given acupuncture treatment at the bilateral hypochondrium (10 mm above iliac crest). The rats in normal group and model group were performed to the same amount of capture stimulation as the acupuncture and non-acupoint groups. After treatment, the hippocampal PKC activity was detected by ELISA. Western blot was used to detect CaMKⅡ expression, and the protein expression of NR2B in CA1, CA3 and DG zones was assayed by immunohistochemical staining.Results Compared with normal group, PKC activity and NR2B expression in the hippocampus significantly decreased in the model group (P<0.01). After the acupuncture treatment, PKC activity increased significantly (P<0.05), and the protein expression of NR2B showed a trend to increase. There was no obvious difference in CaMKⅡ expression among all groups.Conclusion Acupuncture at Zusanli can enhance the activity of hippocampal PKC, a synaptic transmission signal molecule, which maybe one of the important molecular targets for the treatment of VD.
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Objective:To investigate the impairment mechanism of learning and memory ability induced by arsenite through studying the effects of arsenite on the expression level of CaMKⅡ in the hippocampus of offspring mice at different developmental stages. Methods:The model of offspring mice exposed to arsenite (0,15,30 and 60 mg/L NaAsO2) was set up. In postnatal day (PND) 10,20 and 40,the expression levels of CaMKⅡαand CaMKⅡβmRNA in the hippocampus were measured by real-time RT-PCR. Results:In PND 10 and PND 20, the expression levels of CaMKⅡ α and CaMKⅡ β mRNA in the hippocampus of offspring mice exposed to arsenite had no significant difference compared with those in control group. In PND 40, the expression levels of CaMKⅡα mRNA in the hippocampus of offspring mice exposed to arsenite were significantly lower than those in control group, the expression levels of CaMKⅡβ mRNA in the hippocampus of offspring mice exposed to 30 and 60 mg/L arsenite were significantly lower than those in control group (P<0.05) . Conclusion:Arsenite can affect the expression levels of CaMKⅡsubunits in the hippocampus of offspring mice and further may impair the learning and memory ability.
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Aim To observe the analgesic effect of oxymatrine(OMT)and its mechanism.Methods A peripheral mononeuropathy was produced in adult mice by placing loosely constrictive ligatures around the common sciatic nerve.The antinociceptive effects of the OMT were assessed in mechanical allodynia and cold allodynia tests.The CAMKII inhibitor KN-93 and AIP were adopted to investigate the influence of OMT on the analgesic effect and analyze its analgesic mecha-nisms.Western blot was used to evaluate the expres-sions of tCaMKII and pCaMKII protein.Results The intraperitoneal administration of OMT (1 60,80 mg· kg -1 )increased the paw withdrawal threshold in the mechanical allodynia test (P <0.05 ),OMT (1 60, 80,40 mg·kg -1 ,ip)remarkably decreased the paw lifts in the cold allodynia test (P <0.05).Ith KN-93 (1 .25 μg/site),AIP (0.02 μg/site)significantly en-hanced the analgesic effect of OMT (35 mg·kg -1 ) (P <0.01 ).Protein expression of pCaMKII was de-creased by OMT(1 60 mg·kg -1 ).Conclusion OMT has significant protective effects on chronic constriction injury(CCI)in mice,and the effective mechanism of OMT inhibits the expression of CaMKII receptor.
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Objective To investigate the sensory-discriminative and affective-motivational pain response of intrathecal injection of m-AIP,a special inhibitor of CaMKII,in a rat model of chronic constriction injury of sciatic nerve(CCI).Methods Eighteen SD rats were divided randomly into 3 groups(n=6):Group S(sham),Group C(control) and Group m-AIP.Group C and m-AIP were operated with the model of neumpathic pain induced by chronic constriction injury of sciatic nerve; Group S were treated as sham operated rats.Seven days after operation,Group S and C received intrathecal injection of 0.9％ NaCI 20 μl,while Group m-AIP received intrathecal injection of m-AIP 0.5 nmol/20 μl.Escape/avoidance behavior refrecting the affective-motivational dimension of pain was measured on 1.5 h after administration.Rats received pain behavior tests including paw withdrawal mechanical threshold(PWMT) and paw withdrawal thermal latency(PWTL) before and 2 h,4 h,8 h after administration.Results Treatment with m-AIP attenuated escape/avoidance behavior and reversed pain behaviors after CCI.At 2h and 4h after administration,Group m-AIP PWTL((1 1.45 ± 2.04)s,(10.26 ± 1.48)s) and PWMT ((21.15 ±4.32)g,(20.45 ±4.09) g) were increased when compared with Group C PWTL((9.63 ± 1.65)s,(9.30 ±0.73)s),PWMT((13.87 ±2.36)g,(14.80 ±3.12)g)(P＜0.05).Before and8 h after administration,Group m-AIP PWTL,PWMT had no significant difference when compared with Group C (P ＞ 0.05).Conclusion CaMKⅡ may play an important role in sensory and affective pain processing in neuropathic rats.Intrathecal injection of m-AIP can effectively improve pain behaviors and attenuate negative affect.
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BACKGROUND: Calcium calmodulin-dependent kinase Ⅱ (CaMKⅡ) can be more active in patients with left ventricular hypertrophy (LVH), which in turn causes phosphorylation of ryanodine receptors, resulting in inactivation and the instability of intracellular calcium homeostasis. The present study aimed to determine the effect of CaMKⅡ–ryanodine receptor pathway signaling in rabbits with left ventricular hypertrophy and triggered ventricular arrhythmia. METHODS: Forty New Zealand rabbits were randomized into four groups (10 per group): sham group, LVH group, KN-93 group (LVH+KN-93), and ryanodine group (LVH+ryanodine). Rabbits in the LVH, KN-93, and ryanodine groups were used to establish a left ventricular hypertrophy model by the coarctation of the abdominal aorta, while those in the sham group did not undergo the coarctation. After eight weeks, action potentials (APs) were recorded simultaneously in the endocardium and epicardium, and a transmural electrocardiogram (ECG) was also recorded in the rabbit left ventricular wedge model. Drugs were administered to the animals in the KN-93 and ryanodine groups, and the frequency of triggered APs and ventricular tachycardia was recorded after the rabbits were given isoprenaline (1 mol/L) and high-frequency stimulation. RESULTS: The frequency (animals/group) of triggered APs was 0/10 in the sham group, 10/10 in the LVH group, 4/10 in the KN-93 group, and 1/10 in the ryanodine group. The frequencies of ventricular tachycardia were 0/10, 9/10, 3/10, and 1/10, respectively. The frequencies of polymorphic ventricular tachycardia or ventricular fibrillation were 0/10, 7/10, 2/10, and 1/10, respectively. The frequencies of triggered ventricular arrhythmias in the KN-93 and ryanodine groups were much lower than those in the LVH group (P<0.05). CONCLUSIONS: KN-93 and ryanodine can effectively reduce the occurrence of triggered ventricular arrhythmia in rabbits with LVH. The CaMKⅡ–ryanodine signaling pathway can be used as a new means of treating ventricular arrhythmia.
ABSTRACT
Objective To explore the effect of gastrodia elata on learning and memory abilities and synaptic transmission protein(P38,Ca2+ -CaMK Ⅱ α,CREB)expression of hippocampus in model rats with Alzheimer's disease(AD).Methods 24 adult Wistar rats were randomly divided into control group,test group and intervention group.A dose of Aβ1-40 was injected into the hippocampus of rats on test group and intervention group,the control rats were injected with normal saline.When the models were successful,the rats of control group and test groups were given with sodium carboxymethyl cellulose(50g/kg),the rats of intervention group were given with gastrodia elata powder( 50 g/kg),lasting 15 days,Morris water maze test was used for learning and memory abilities study.The expression of P38,Ca2+-CaMK Ⅱ α and CREB protein were detected by immunohistochemistry method.Results Behavioral tests showed the mean escape latencies and search time of test group were obviously increased than those of control group and intervention group,the percentage of search distance on test groups was less than that of control group and intervention group(P ＜ 0.01 ).Immunohistochemistry results showed P38,Ca2+- CaMK Ⅱ α and CREB positive cells and optical density in hippocampus CA1 on test group were less than those of control group and intervention group ( all P ＜ 0.01 ) ( P38:58.92 ± 10.82,0.208 ± 0.037 ; Ca2+-CaMK Ⅱ α:72.38 ± 14.67,0.174 ± 0.036 ; CREB:53.86 ±5.31,0.161 ±0.043 in test group;P38:87.32 ±9.56,0.371 ±0.046 ; Ca2+ -CaMK Ⅱ α:98.16 ± 16.29,0.283 ± 0.051 ; CREB:86.76 ± 7.73,0.356 ± 0.052 in intervention group; P38:102.54 ± 16.73,0.563 ± 0.078 ; Ca2 + -CaMK Ⅱ α:123.46 ± 17.65,0.436 ± 0.057 ; CREB:125.43 ±9.16,0.524 ± 0.057 in control group ).Conclusion Gastrodia elata can treat AD by increasing expression of P38,Ca2 + -CaMK Ⅱ α and CREB.