中国医师杂志
中國醫師雜誌
중국의사잡지
JOURNAL OF CHINESE PHYSICIAN
2014年
11期
1477-1482
,共6页
李晓媚%黄程%何玉莲%方伟进%熊燕
李曉媚%黃程%何玉蓮%方偉進%熊燕
리효미%황정%하옥련%방위진%웅연
寒冷%心血管系统%肌,骨骼/生理学%肌收缩%大鼠,Sprague-Dawley
寒冷%心血管繫統%肌,骨骼/生理學%肌收縮%大鼠,Sprague-Dawley
한랭%심혈관계통%기,골격/생이학%기수축%대서,Sprague-Dawley
Chills%Cardiovascular system%Muscle,skeletal/physiology%Muscle contraction%Rats,Sprague-Dawley
目的 观察不同时程寒冷对大鼠心血管功能与骨骼肌收缩力的影响.方法 取成年雄性SD大鼠,制备不同时程的寒冷动物模型,实验分(1)正常对照组、(2)寒冷12 h组、(3)寒冷24 h组、(4)寒冷48 h组;各寒冷组大鼠均置于4℃环境中,但可自由进食和饮水.经上述处理后,麻醉下迅速分离大鼠心脏、胸主动脉、比目鱼肌和趾长伸肌,分别连实验灌流装置和数据记录系统;离体心脏采用Langendorff灌流,先记录冠脉流量(CF)、左心室平均收缩压(mLVSP)、平均舒张压(mLVDP)、左心室平均压(mLVP)和左室内压最大上升与下降速率(±dP/dt max)等心功能指标,再进行心脏缺血-再灌注,并记录上述心功能指标的变化;用器官浴槽法检测主动脉环收缩与内皮依赖性舒张反应;用电刺激法分别检测比目鱼肌和趾长伸肌的单次和强直收缩的最大张力.结果 与正常对照组相比,寒冷24～48 h明显降低大鼠CF[(9.0±1.7) ml/g和(9.8±1.3)ml/g vs(11.6±1.2)ml/g,P＜0.05],寒冷48 h还增加mLVSP(P＜0.01)和mLVP(P＜0.05);在心肌缺血再灌注后,寒冷12～ 48 h均可缩短大鼠心脏复跳时间(均P ＜0.01),但寒冷24 ～48 h明显升高缺血再灌注后mLVDP和mLVP(均P＜0.01);在血管环实验中,寒冷24 ～48 h均可降低血管环对60 mmol/L氯化钾[(0.63±0.13)g和(0.79±0.11)g vs (1.28±0.17)g,P＜0.01]和1μmol/L苯肾上腺素[(0.62±0.18)g和(0.68±0.13)g vs (1.25 ±0.18)g,P＜0.01]诱导的血管收缩反应,但增加血管环对低浓度(3×10-8 ～3×10-7)乙酰胆碱诱导的内皮依赖性舒张反应(P＜0.05);寒冷48 h还降低了比目鱼肌和趾长伸肌对电刺激诱导的强直收缩张力[(4.14±0.62) N/cm2 vs (5.50±0.75) N/cm2,P ＜0.05;(3.00±0.57)N/cm2 vs (4.70±0.85) N/cm2,P ＜0.01].结论 4℃寒冷24 ～ 48 h可降低冠脉血流量,可增强大鼠心脏对缺血再灌注损伤的耐受;寒冷24～48 h可降低血管收缩并增加ACh诱导血管内皮依赖性舒张的敏感性;寒冷48 h减弱骨骼肌对电刺激的收缩功能.
目的 觀察不同時程寒冷對大鼠心血管功能與骨骼肌收縮力的影響.方法 取成年雄性SD大鼠,製備不同時程的寒冷動物模型,實驗分(1)正常對照組、(2)寒冷12 h組、(3)寒冷24 h組、(4)寒冷48 h組;各寒冷組大鼠均置于4℃環境中,但可自由進食和飲水.經上述處理後,痳醉下迅速分離大鼠心髒、胸主動脈、比目魚肌和趾長伸肌,分彆連實驗灌流裝置和數據記錄繫統;離體心髒採用Langendorff灌流,先記錄冠脈流量(CF)、左心室平均收縮壓(mLVSP)、平均舒張壓(mLVDP)、左心室平均壓(mLVP)和左室內壓最大上升與下降速率(±dP/dt max)等心功能指標,再進行心髒缺血-再灌註,併記錄上述心功能指標的變化;用器官浴槽法檢測主動脈環收縮與內皮依賴性舒張反應;用電刺激法分彆檢測比目魚肌和趾長伸肌的單次和彊直收縮的最大張力.結果 與正常對照組相比,寒冷24～48 h明顯降低大鼠CF[(9.0±1.7) ml/g和(9.8±1.3)ml/g vs(11.6±1.2)ml/g,P＜0.05],寒冷48 h還增加mLVSP(P＜0.01)和mLVP(P＜0.05);在心肌缺血再灌註後,寒冷12～ 48 h均可縮短大鼠心髒複跳時間(均P ＜0.01),但寒冷24 ～48 h明顯升高缺血再灌註後mLVDP和mLVP(均P＜0.01);在血管環實驗中,寒冷24 ～48 h均可降低血管環對60 mmol/L氯化鉀[(0.63±0.13)g和(0.79±0.11)g vs (1.28±0.17)g,P＜0.01]和1μmol/L苯腎上腺素[(0.62±0.18)g和(0.68±0.13)g vs (1.25 ±0.18)g,P＜0.01]誘導的血管收縮反應,但增加血管環對低濃度(3×10-8 ～3×10-7)乙酰膽堿誘導的內皮依賴性舒張反應(P＜0.05);寒冷48 h還降低瞭比目魚肌和趾長伸肌對電刺激誘導的彊直收縮張力[(4.14±0.62) N/cm2 vs (5.50±0.75) N/cm2,P ＜0.05;(3.00±0.57)N/cm2 vs (4.70±0.85) N/cm2,P ＜0.01].結論 4℃寒冷24 ～ 48 h可降低冠脈血流量,可增彊大鼠心髒對缺血再灌註損傷的耐受;寒冷24～48 h可降低血管收縮併增加ACh誘導血管內皮依賴性舒張的敏感性;寒冷48 h減弱骨骼肌對電刺激的收縮功能.
목적 관찰불동시정한랭대대서심혈관공능여골격기수축력적영향.방법 취성년웅성SD대서,제비불동시정적한랭동물모형,실험분(1)정상대조조、(2)한랭12 h조、(3)한랭24 h조、(4)한랭48 h조;각한랭조대서균치우4℃배경중,단가자유진식화음수.경상술처리후,마취하신속분리대서심장、흉주동맥、비목어기화지장신기,분별련실험관류장치화수거기록계통;리체심장채용Langendorff관류,선기록관맥류량(CF)、좌심실평균수축압(mLVSP)、평균서장압(mLVDP)、좌심실평균압(mLVP)화좌실내압최대상승여하강속솔(±dP/dt max)등심공능지표,재진행심장결혈-재관주,병기록상술심공능지표적변화;용기관욕조법검측주동맥배수축여내피의뢰성서장반응;용전자격법분별검측비목어기화지장신기적단차화강직수축적최대장력.결과 여정상대조조상비,한랭24～48 h명현강저대서CF[(9.0±1.7) ml/g화(9.8±1.3)ml/g vs(11.6±1.2)ml/g,P＜0.05],한랭48 h환증가mLVSP(P＜0.01)화mLVP(P＜0.05);재심기결혈재관주후,한랭12～ 48 h균가축단대서심장복도시간(균P ＜0.01),단한랭24 ～48 h명현승고결혈재관주후mLVDP화mLVP(균P＜0.01);재혈관배실험중,한랭24 ～48 h균가강저혈관배대60 mmol/L록화갑[(0.63±0.13)g화(0.79±0.11)g vs (1.28±0.17)g,P＜0.01]화1μmol/L분신상선소[(0.62±0.18)g화(0.68±0.13)g vs (1.25 ±0.18)g,P＜0.01]유도적혈관수축반응,단증가혈관배대저농도(3×10-8 ～3×10-7)을선담감유도적내피의뢰성서장반응(P＜0.05);한랭48 h환강저료비목어기화지장신기대전자격유도적강직수축장력[(4.14±0.62) N/cm2 vs (5.50±0.75) N/cm2,P ＜0.05;(3.00±0.57)N/cm2 vs (4.70±0.85) N/cm2,P ＜0.01].결론 4℃한랭24 ～ 48 h가강저관맥혈류량,가증강대서심장대결혈재관주손상적내수;한랭24～48 h가강저혈관수축병증가ACh유도혈관내피의뢰성서장적민감성;한랭48 h감약골격기대전자격적수축공능.
Objective To investigate the effects of cold exposure with different time courses on cardiovascular function and skeletal muscle contraction in Sprague-Dawley (SD) rats.Methods The male SD rats were randomly divided into control,12-h cold,24-h cold,and 48-h cold groups.The rats in all cold group were maintained in 4 ℃ environment for indicated time and allowed free access to standard rat chow and water ad libitum.After the animal model was established,the heart,thoracic aorta,soleus,and extensor digitorum longus (EDL) were rapidly isolated from rats under anesthesia and then fixed into the respective organ perfusion system that was connected to physiological recorders and data acquisition system.Lanendorff heart persusion was used to detect some parameters of cardiac function,such as coronary flow (CF),mean left ventricular systolic pressure (mLVSP),mean left ventricular diastolic pressure (mLVDP) and maximum ascending and declining rate of left ventricular pressure (± dp/dt max) ; and then the heart was suffered from 30 min ischemia followed by 60 min reperfusion,the changes of above cardiac function indexes were recorded again.Organ bath method was employed to detect contraction response to potassium chloride (KCl) or phenylephrine (PE) and endothelium-dependent relation responses to acetylcholine (ACh) of aortic rings.The twitch tension,titanic tension,and fatigue test of soleus and EDL were examined by electrical stimulation to reflect contractive function of skeletal muscle.Results The coronary flow (CF) were significantly reduced in 24-h and 48-h cold groups compared to control group [(9.0 ± 1.7) ml/g and (9.8 ± 1.3) ml/g vs (11.6 ± 1.2) ml/g,P ＜ 0.05] ; 48-h cold exposure also showed significantly increased mLVSP (P ＜0.01) and mLVP (P ＜ 0.05) of rats.After ischemia-reperfusion,the heart re-beat time was shorter in all cold exposure groups (all P ＜ 0.01),mLVP and mLVDP were higher in 24-h and 48-h cold group than control group (all P ＜ 0.01).The contraction of aortic rings responses to 60 mmol/L KCl [(0.63 ±0.13) g and (0.79 ±0.11)g vs (1.28±0.17)g,P ＜0.01] and 1 μmol/L PE [(0.62 ±0.18)g and (0.68 ±0.13)g vs (1.25 ± 0.18)g,P ＜ 0.01] were decreased while the endothelium-dependent relaxation responses to low concentration ACh (3 × 10-8 ～ 3 × 10-7) were increased in 24-h and 48-h cold groups relative to control group (all P ＜ 0.05).The 48-h cold also reduced titanic tension of SOL and EDL in comparison with control [(4.14 ± 0.62) N/cm2 vs (5.50 ± 0.75) N/cm2,P ＜ 0.05 and (3.00 ± 0.57) N/ cm2 vs (4.70 ± 0.85) N/cm2,P ＜ 0.01].Conclusions 24 ～ 48 h cold exposure could reduce CF but enhance the tolerance of heart from rats to ischemia reperfusion injury and also decrease the contraction of aortic rings response to KCl or PE but increase the sensitive responses to ACh of aortic rings from rats.The 48-h cold could decrease the contraction of skeletal muscle elicited by electrical stimulation.
