慢性间歇低氧对阻塞性睡眠呼吸暂停模型兔左室心肌收缩功能的影响  

Effects of chronic intermittent hypoxia on left ventricular myocardial contractibility in a rabbit model of obstructive sleep apnea

作　　者：许利芳[1] 蔡永芳[2] 胡克[1] 汤思[1] 周秀芳[1] 李慧敏[1] 

机构地区：[1]武汉大学人民医院呼吸科,430060 [2]湖北三峡职业技术学院附属医院

出　　处：《中华医学杂志》2017年第32期2528-2532,共5页National Medical Journal of China

基　　金：国家自然科学基金（81070065,81370181）;湖北省自然科学基金（2015CFB410）

摘　　要：目的探讨慢性间歇低氧（CIH）对阻塞性睡眠呼吸暂停（OSA）模型兔左室心肌收缩功能的影响。方法将24只成年新西兰大白兔按随机数字表法随机分为手术组、假手术组及对照组各8只。手术组按照重复关闭与开放上气道的方法建立OSA兔模型，每天进行气道关闭和开放，每次上气道关闭15s、开放75s，每90秒循环1次，每天8h，连续3个月。对假手术组进行相同的手术处理，但不造成气道阻塞；对照组不予手术处理。监测实验前后血压及左室功能变化，以实时荧光定量PCR法检测实验后各组心肌肌球蛋白重链（α—MHC和β-MHC）mRNA的相对表达量。结果与造模前相比，3个月后，手术组兔出现嗜睡等表现，血压升高[（114．25±4．20）比（93．88±2．10）mmHg（1mmHg=0．133kPa），P〈0．01]。手术组左室收缩末容积和舒张末容积显著高于假手术组及对照组[（6．05±1．62）比（2．83±0．49）、（2．74±0．32）ml和（1．61±0．78）比（0．83±0．13）、（0．82±0．10）ml，均P〈0．001]，而左室射血分数、左室内径缩短率及每搏输出量均显著低于其他两组[（63．9±4．2）％比（74．3±2．5）％和（75．8±3．8）％、（32．2±2．1）％比（41．8±1．8）％和（42．1±1．8）％、（1．46±0．13）比（1．93±0．21）和（1．98±0．24）ml／s，均P〈0．001]；同时，左室内压最大上升速率、最大下降速率均显著低于假手术组和对照组[（4154±360）比（6802±492）和（6759±206）mmHg／s、（4994±621）比（6330±314）和（6591±225）mmHg／s，均P〈0．001]，而左室舒张末压显著高于其他两组[（6．5±1．6）比（3．3±0．8）、（3．2±0．9）mmHg，P〈0．001]。手术组左室心肌组织α-MHC mRNA相对表达量显著低于其他两组，而β—MHC mRNA相对表达量显著高于其他两组（均P〈0．05）。对照组与假手术组心功能相关指标、左室�Objective To explore the effects of chronic intermittent hypoxia （CIH） on left ventricular myocardial contractibility in a rabbit model of obstructive sleep apnea （OSA）. Methods Based on random number table, twenty-four rabbits were randomly divided into three groups ： operation, sham, and control groups, each with 8 rabbits. The rabbit model for OSA in operation group was established by repeatedly closing the airway and then reopening it. Upper airway obstructions were conducted on rabbits every day, which were alternately closed for 15 s and then reopened for 75 s in a 90 s-long cycle, for 8 h each day over 3 months. The sham rabbits were subjected to the same surgical procedure but no airway obstructions were applied. The control animals were subjected to no intervention. The blood pressure, left ventricular function parameters were assessed before and after the experiment. And the relative expressions of myosin heavy chain α/β （α-MHC and β-MHC） mRNAs in myocardium were observed for all rabbits by real time fluorescent quantitative polymerase chain reaction 3 months later. Results After 3 months, all rabbits in the operation group manifested sleepiness and the blood pressure rose gradually [ （114. 25 ±4. 20） vs （93.88 ±2. 10） mmHg, P 〈 0.01 ]. Compared with the sham operation and the control groups, the left ventricular end-systolic volume [ （6. 05 ± 1.62） vs （2. 83 ±0.49） and （2. 74 ±0. 32） ml, P 〈0. 001 ] and the left ventricular end-diastolic volume [ （ 1.61 ± 0. 78 ） vs （ 0. 83 ± 0. 13 ） and （ 0. 82 ± 0. 10 ） ml ] in operation group were obviously higher, the left ventrieular ejection fraction [ （63.9 ±4. 2） % vs （74. 3 ± 2.5） % and （75.8 ±3.8） %], left ventricular fractional shortening [（32.2 ±2. 1） % vs （41.8 ± 1.8） % and （42.1 ±1.8） %] and stroke volume [（1.46 ±0.13） vs （1.93 ±0.21） and （1.98 ± 0. 24） ml/s] were decreased （all P 〈0. 001 ）. Besides, the maximal rate of the increase of left ven

关 键 词：睡眠呼吸暂停 阻塞性 细胞低氧 心肌收缩 兔 

分 类 号：R-332[医药卫生] R766