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Objective:To study the antidepressant effect of Baihe Zhimu decoction (BZD)and its influence in the key factors (CaM,CaMKⅡ,CREB)of CaM signaling pathway in hippocampus of the rats with depression,and to explore the antidepressant effect of BZD. Methods:Fifty rats were divided into control group,model group, fluoxetine group,low and high doses of BDZ groups (n = 10).Expect for control group,all the rats in other groups were made depression models by means of chronic unpredictable mild stress along with isolated raising,for 21 d.Then the rats were fed with NS, fluoxetine (1.8 mg · kg-1 ), and BZD (1.5 and 3.0 g · kg-1 ), respectively;for 28 d.The learning and memory ability,autonomous activities and the fixed time in 5 min of the rats were tested by Morris water amaze,Open-field Test and Forced Swimming Test respectively. The damage and repair status of hippocampal neurons were observed by Nissl staining method;the expression levels of CaM,CaMKⅡ protein,CREB mRNA in hippocampus of the rats were detected by Western blotting and RT-PCR method. Results:Compared with model group,the total time of rats in the platform quadrant of Morris water maze in BZD groups and fluoxetine group,the total distance and the number of crossing platform were increased (P <0.05 or P <0.01),and the time of first crossing platform were shortened (P <0.01);the total scores in open field test were increased (P <0.01),the fixed time with 5 min in the forced swimming test was shortened (P <0.05 or P <0.01).Compared with fluoxetine group,the fixed time within 5 min of the rats in swimming test was shortened (P <0.05).The result of Nissl staining showed that the hippocampal neuron injury in BZD groups and fluoxetine group was improved compared with model group.The molecular test results showed that the CaM and CaMKⅡprotein expression levels in hippocampus of the rats in BZD groups and fluoxetine group were increased compared with model group (P < 0.05 or P < 0.01).Compared with model group,the CREB mRNA expression levels in fluoxetime group and BZD groups were increased (P < 0.05 or P < 0.01).Conclusion:BZD has antidepressant effect and can improve the hippocampal neuron injury of the rats with depression and its mechanism is related to increasing the expression levels of CaM,CaMKⅡ and CREB in hippocampus CAM signaling pathway of the rats.
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Objective To investigate the effect of warm needling on learning and memory abilities and the calmodulin kinaseⅡ (CaMKⅡ) content of prefrontal cortex area in morphine withdrawal rats andexplore the mechanism of its action. Methods Forty clean-grade male SD rats were randomly allocated to control, model, manual needling and warm needling groups, 10rats each. A SD rat model of morphine addiction and withdrawal was made by dorsal subcutaneous injection of day-by-day incremental morphine and rapid withdrawal with Naloxone after addiction. Learning and memory abilities were tested using a Morris water maze and the CaMKⅡ content of prefrontal cortex area was measured by an immunohistochemical method in every group of rats.Results There were statistically significant differences in mean platform escape latency, the number of platform crossing and the CaMKⅡ content of PFC area between the control, manual needling or warm needling group of rats and the model group (P<0.01). There were statistically significant differences in mean platform escape latency, the number of platform crossing and the CaMKⅡ content of PFC area between the warm needling and manual needling groups (P<0.05).Conclusions Warm needling treatment can restore learning and memory abilities in morphine withdrawal rats. The mechanism of its action may be related to an increase in the CaMKⅡ content of prefrontal cortex area.
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Objective To investigate the changes of calmodulin kinase Ⅱ (CaMK Ⅱ) and cAMP responsive element binding protein(CREB) expressing in primary cultured hippocampal neurons and its relationship with learning and memory deficit after 2000 μW/cm2 electromagnetic radiation.Methods Primary cultured hippocampal neurons in vitro were randomly divided into normal control group,sham-radiated group,and 1 h/d,2 h/d,3 h/dradiation groups.The neurons in the radiation groups were received microwave exposure of 2000 μW/cm2.The change of CaMK Ⅱ and CREB protein in hippocampal neurons of each group of rats were measured with western blot,and the expression of CaMK Ⅱ and CREB mRNA in hippocampus were determined by RT-PCR.Results Compared with control group((0.78 ± 0.07),(0.62 ± 0.12)),the expression of CaMK Ⅱ protein (1 h/d(0.59 ±0.05),2h/d(0.44 ±0.08),3h/d(0.18 ±0.04)) and its mRNA(1h/d(0.41 ±0.08),2h/d(0.34 ±0.04),3h/d(0.24 ±0.02)) was obviously decreased (P＜0.05).Compared with control group((0.69 ±0.10),(0.80 ±0.12)),the expression of CREB protein(1h/d(0.49 ±0.05),2h/d(0.4 ±0.04),3h/d(0.17 ±0.03))and its mRNA (1 h/d (0.68 ± 0.11),2h/d (0.53 ± 0.08),3h/d (0.30 ± 0.03)) was obviously decreased after radiation(P＜0.05).Conclusion Electromagnetic radiation of 2000 μW/cm2 exposure could weaken the learning and memory abilities of rats and the decreases in the expression of CaMK Ⅱ and CREB protein and their mRNA in hippocampus may be involved in the pathophysiological process of learning and memory deficit.
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Objective To investigate the effect of the calmodulin kinase Ⅱ Inhibitor KN-93 on L-typecalcium current(ICa,L)and intracellular calcium concentration([Ca2+]i)in hypertrophic cardiac myocytes.Methods Forty-eight female New Zealand white rabbits were randomized(random number)into four groups(12 animals in each group):the sham operation group(sham group),the left ventricular hypertrophy group(LVH group),the myocardial hypertrophy + KN-93 group(KN-93 group),and the myocardial hypertrophy + KN-92 group(KN-92 group).Myocardial hypertrophy in the rabbits was established by coarctation of the abdominal aorta.In the sham group,the abdominal aorta was dissociated without coarctation.Eight weeks after coarctation,single ventricular myocytes were isolated by enzymaticdissociation,and ICa,L was recorded using perforated-patch recording(PPR)techniques.[Ca2+]i was measured using single-cell calcium imaging with the fluorescence calcium indicator dye fura-2/AM.Results Cardiac hypertrophy was successfully established after 8 weeks of coarctation of the abdominal aorta.The peak ICa,L in the LVH group and the sham group was(1.38 ± 0.3)nA and(0.87 ± 0.1)nA at 0 mV,respectively(P ＜0.01,n =12).There was no significant difference in Ica,L density between the LVH group and the sham group[(6.7 ±1.0)pA/pF vs.(6.3±0.7)pA/pF; P≥0.05,n=12].The addition of either KN-92(0.5 μmol/L)or KN-93(0.5 μmol/L)to the perfusing solution caused a modest steady-state inhibition of peak ICaL(9.4％ ±2.8％,KN-92; 10.5％ ±3％,KN-93)(P≥0.05,n =12)at 0 mV.However,at a higher concentration(1 μmol/L),KN-93 more potently inhibited peak ICa,L(40％±4.9％)compared to KN-92(13.4％ ± 3.7％ ; P ＜ 0.01,n =12).Resting[Ca2+]i levels in fura-2-loaded myocytes isolated from the sham,LVH,KN-92,and KN-93 groups were(98 ± 12.3)nmol/L,(154 ± 26.2)nmol/L,(147 ± 29.6)nmol/L,and(108 ± 21.2)nmol/L,respectively.Conclusions The CaMK Ⅱ specific inhibitor,KN-93,can effectively block ICa,L and reduce intracellular calcium overload in hypertrophic cardiac myocytes.This action may account for the antiarrhythmic effect of KN-93 in hypertrophic ventricular myocardium.
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Objective To determine the effect of calmodulin-dependent kinase Ⅱ (CaMK Ⅱ ) -ryanodinereceptor pathway signaling in rabbits with left ventricular bypertrophy (LVH) and triggered ventricular arrhythmia.Methods Forty New Zealand rabbits were randomized into four groups ( n =10 per group):the sham operation group,LVH group,KN-93 (CaMKⅡ inhibitor) group (LVH + KN-93),and the ryanodinegroup ( LVH + ryanodine).Rabbits in the LVH,KN-93,and ryanodinegroups were used to establish a left ventricular hypertrophy model by the coarctation of the abdominal aorta,while the rabbits in the sham operation group did not have the coarctation.After eight weeks,action potentials (APs) were recorded simultaneously in the endocardium and epicardium,and transmural electrocardiogram (ECG) was also recorded in the wedge shaped models of rabbits' left ventricular myocardium.Drugs were administered to animals in the KN-93 and ryanodinegroups respectively,and the frequency of triggered APs and ventricular tachycardia were recorded after isoprenaline ( 1 μmol/L),and high-frequency electrical stimulation were given to rabbits.Results The incidences (animals/group) of triggered APs were:sham,0/10 ; LVH,10/10; KN-93,4/10; and ryanodine,1/10.The incidences of ventricular tachycardia induced were 0/10,9/10,3/10,and 1/10,respectively.The incidences of triggered ventricular arrhythmias in the KN-93 group and ryanodine groups tachycardia or ventricular fibrillation were 0/10,7/10,2/10,and 1/10,respectively.The incidences of triggered ventricular arrhythmias in the KN-93 group and ryanodine groups were much lower than that in the LVH group (P ＜ 0.05).Conclusions KN-93 and ryanodinecan effectively reduce the occurrence of triggered ventricular arrhythmia in rabbits with LVH.The CaMK Ⅱ-ryanodine signaling pathway can be used as a novel target site of treating ventricular arrhythmia.