1.Investigation on resources and Utilization of marine medicinal animals in Zhoushan Sea Area
Zhongmiao JIANG ; Guoping ZHENG ; Musen CHEN ;
Chinese Journal of Marine Drugs 1994;0(01):-
OBJECTIVE Making knowledge of the marine medication animal species distribution and the resource situation in Zhoushan sea area. METHODS According the experiment explored, the marine animal specimen collected, checked, corrected. RESULTS There were about 103 species marine animal for medicating, included 4 species of Coelenterata, 3 species of Annelida, 14 species of Arthropoda, 21 species of Mollusca, 55 species of Vertebrata, 6 species of Echinodermate . CONCLUSIONS The reliable base of protecting ecological environment of marine organisms and exploiting resources of marine medicinal animals rationally were founded.
2.The effects of calmodulin kinase Ⅱ inhibitor on hypertrophic cardiac myocytes
Jun KE ; Feng CHEN ; Xin XIAO ; Musen DAI ; Xiaoping WANG ; Bin CHEN ; Min CHEN ; Cuntai ZHANG
Chinese Journal of Emergency Medicine 2012;21(2):151-155
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.
3.Dynamic evaluation of myocardial dysfunction in rats after cardiopulmonary resuscitation
Shen ZHAO ; Yumin HE ; Bing XU ; Heng LI ; Musen DAI ; Feng CHEN
Chinese Journal of Emergency Medicine 2017;26(1):44-50
Objective To observe the dynamic changes of myocardial structure and dysfunction during post-resuscitation period in order to establish a rat mode of post-resuscitation myocardial dysfunction after cardiac arrest resulted from electric stimulation-induced ventricular fibrillation (VF) and cardiopulmonary resuscitation (CPR).Methods A total of 40 male Sprague-Dawley (SD) rats were randomly (random number) assigned into post-resuscitation (PR) 4 h,PR 12 h,PR 24 h,PR 72 h and sham groups.VF was induced by an alternating electric current delivered to the right ventricular endocardium and untreated for 8 min.Biphasic waveform defibrillation was attempted and mechanical ventilation was synchronized after 6 min of CPR.Myocardial function was assessed with serum myocardial enzyme activity,echocardiography,mitochondrial respiratory function and histopathologic findings at different intervals.Results Thirty-two animals were successfully resuscitated with restoration of spontaneous circulation (ROSC) in 86% (32/37) rats.Compared with sham group,severe systolic and diastolic heart failure were found at 4 h after ROSC and then gradually improved without significant difference (P >0.05) in ejection fraction at PR 72 h after ROSC was found,whereas thickened ventricular wall and increased myocardial performance index as well as interstitial proliferation were observed at 72 h after ROSC.Conclusions A rat model of post-resuscitation myocardial dysfunction after cardiac arrest resulted from electric stimulation-induced VF and CPR was successfully established.
4.Roles of CaMK H -ryanodine receptor signal transduction pathways in triggered ventricular arrhythnia of rabbits with myocardial hypertrophy
Hun KE ; Xing XIAO ; Feng CHEN ; Li HE ; Musen DAI ; Xiaopin WANG ; Bing CHEN ; Min CHEN ; Cuntai ZHANG
Chinese Journal of Emergency Medicine 2012;21(4):392-396
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.
5.Effects of calmodulin-dependent protein kinase II inhibitor, KN-93, on electrophysiological features of rabbit hypertrophic cardiac myocytes.
Jun, KE ; Feng, CHEN ; Cuntai, ZHANG ; Xing, XIAO ; Jing, TU ; Musen, DAI ; Xiaoping, WANG ; Bing, CHEN ; Min, CHEN
Journal of Huazhong University of Science and Technology (Medical Sciences) 2012;32(4):485-9
Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related. The aim of this study was to determine the effects of the calmodulin-dependent protein kinase (CaMK) II inhibitor, KN-93, on L-type calcium current (I(Ca, L)) and early after-depolarizations (EADs) in hypertrophic cardiomyocytes. A rabbit model of myocardial hypertrophy was constructed through abdominal aortic coarctation (LVH group). The control group (sham group) received a sham operation, in which the abdominal aortic was dissected but not coarcted. Eight weeks later, the degree of left ventricular hypertrophy (LVH) was evaluated using echocardiography. Individual cardiomyocyte was isolated through collagenase digestion. Action potentials (APs) and I(Ca, L) were recorded using the perforated patch clamp technique. APs were recorded under current clamp conditions and I(Ca, L) was recorded under voltage clamp conditions. The incidence of EADs and I(ca, L) in the hypertrophic cardiomyocytes were observed under the conditions of low potassium (2 mmol/L), low magnesium (0.25 mmol/L) Tyrode's solution perfusion, and slow frequency (0.25-0.5 Hz) electrical stimulation. The incidence of EADs and I(ca, L) in the hypertrophic cardiomyocytes were also evaluated after treatment with different concentrations of KN-92 (KN-92 group) and KN-93 (KN-93 group). Eight weeks later, the model was successfully established. Under the conditions of low potassium, low magnesium Tyrode's solution perfusion, and slow frequency electrical stimulation, the incidence of EADs was 0/12, 11/12, 10/12, and 5/12 in sham group, LVH group, KN-92 group (0.5 μmol/L), and KN-93 group (0.5 μmol/L), respectively. When the drug concentration was increased to 1 μmol/L in KN-92 group and KN-93 group, the incidence of EADs was 10/12 and 2/12, respectively. At 0 mV, the current density was 6.7±1.0 and 6.3±0.7 PA·PF(-1) in LVH group and sham group, respectively (P>0.05, n=12). When the drug concentration was 0.5 μmol/L in KN-92 and KN-93 groups, the peak I(Ca, L) at 0 mV was decreased by (9.4±2.8)% and (10.5±3.0)% in the hypertrophic cardiomyocytes of the two groups, respectively (P>0.05, n=12). When the drug concentration was increased to 1 μmol/L, the peak I(Ca, L) values were lowered by (13.4±3.7)% and (40±4.9)%, respectively (P<0.01, n=12). KN-93, a specific inhibitor of CaMKII, can effectively inhibit the occurrence of EADs in hypertrophic cardiomyocytes partially by suppressing I(Ca, L), which may be the main action mechanism of KN-93 antagonizing the occurrence of ventricular arrhythmias in hypertrophic myocardium.
6.Orthogonal test analysis of compressive strength of porous hydroxylapatite prepared by gel-casting process.
Yanjun HAN ; Musen LI ; Yupeng LÜ ; Yunjing SONG ; Y CHEN ; H LOW
Journal of Biomedical Engineering 2004;21(5):704-707
Porous hydroxylapatite (HA) has excellent osseous inductive ability. It has been prepared by gel-casting process, which is feasible and can make complex ceramic material. According to the result of orthogonal test based on the compressive strength, the order and the level of the factors, including monomer HA, initiator MBAM, catalyst APS and water, were dealt with. The effects of drying and sintering technique on the properties of porous hydroxylapatite were also researched. The results showed that the order of every factor in the gel-casting process is as follows, AM-APS, MBAM, H2O. Based on the determined level of each factor, the suitable slurry constituents and drying and sintering technologies were selected, and the porous hydroxylapatite with compressive strength of 6-7 MPa was produced.
Biocompatible Materials
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chemistry
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Bone Substitutes
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chemistry
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Compressive Strength
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Durapatite
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chemical synthesis
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chemistry
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Gels
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Humans
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Materials Testing
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methods
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Porosity
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Surface Properties
7.Effects of calmodulin-dependent protein kinase II inhibitor, KN-93, on electrophysiological features of rabbit hypertrophic cardiac myocytes.
Jun KE ; Feng CHEN ; Cuntai ZHANG ; Xing XIAO ; Jing TU ; Musen DAI ; Xiaoping WANG ; Bing CHEN ; Min CHEN
Journal of Huazhong University of Science and Technology (Medical Sciences) 2012;32(4):485-489
Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related. The aim of this study was to determine the effects of the calmodulin-dependent protein kinase (CaMK) II inhibitor, KN-93, on L-type calcium current (I(Ca, L)) and early after-depolarizations (EADs) in hypertrophic cardiomyocytes. A rabbit model of myocardial hypertrophy was constructed through abdominal aortic coarctation (LVH group). The control group (sham group) received a sham operation, in which the abdominal aortic was dissected but not coarcted. Eight weeks later, the degree of left ventricular hypertrophy (LVH) was evaluated using echocardiography. Individual cardiomyocyte was isolated through collagenase digestion. Action potentials (APs) and I(Ca, L) were recorded using the perforated patch clamp technique. APs were recorded under current clamp conditions and I(Ca, L) was recorded under voltage clamp conditions. The incidence of EADs and I(ca, L) in the hypertrophic cardiomyocytes were observed under the conditions of low potassium (2 mmol/L), low magnesium (0.25 mmol/L) Tyrode's solution perfusion, and slow frequency (0.25-0.5 Hz) electrical stimulation. The incidence of EADs and I(ca, L) in the hypertrophic cardiomyocytes were also evaluated after treatment with different concentrations of KN-92 (KN-92 group) and KN-93 (KN-93 group). Eight weeks later, the model was successfully established. Under the conditions of low potassium, low magnesium Tyrode's solution perfusion, and slow frequency electrical stimulation, the incidence of EADs was 0/12, 11/12, 10/12, and 5/12 in sham group, LVH group, KN-92 group (0.5 μmol/L), and KN-93 group (0.5 μmol/L), respectively. When the drug concentration was increased to 1 μmol/L in KN-92 group and KN-93 group, the incidence of EADs was 10/12 and 2/12, respectively. At 0 mV, the current density was 6.7±1.0 and 6.3±0.7 PA·PF(-1) in LVH group and sham group, respectively (P>0.05, n=12). When the drug concentration was 0.5 μmol/L in KN-92 and KN-93 groups, the peak I(Ca, L) at 0 mV was decreased by (9.4±2.8)% and (10.5±3.0)% in the hypertrophic cardiomyocytes of the two groups, respectively (P>0.05, n=12). When the drug concentration was increased to 1 μmol/L, the peak I(Ca, L) values were lowered by (13.4±3.7)% and (40±4.9)%, respectively (P<0.01, n=12). KN-93, a specific inhibitor of CaMKII, can effectively inhibit the occurrence of EADs in hypertrophic cardiomyocytes partially by suppressing I(Ca, L), which may be the main action mechanism of KN-93 antagonizing the occurrence of ventricular arrhythmias in hypertrophic myocardium.
Animals
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Benzylamines
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pharmacology
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Calcium-Calmodulin-Dependent Protein Kinase Type 2
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antagonists & inhibitors
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metabolism
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Cardiomegaly
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metabolism
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physiopathology
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Female
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Myocytes, Cardiac
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drug effects
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metabolism
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physiology
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Rabbits
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Sulfonamides
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pharmacology