不同β-肾上腺素能受体对低氧应激大鼠心脏舒缩功能的影响  

Effects of different β-adrenergic receptors on cardiac systolic and diastolic functions in hypoxic stress rats

作　　者：纪巧荣 张昱[1] 刘杰[1] 曹成珠[1] 周振[1] 袁周阳 张伟[1] JI Qiao-rong;ZHANG Yu;LIU Jie;CAO Cheng-zhu;ZHOU Zhen;YUAN Zhou-yang;ZHANG Wei(Medical College of Qinghai University,The Key Laboratory of High Altitude Medical Application of Qinghai Province,Xining 810001,China.)

机构地区：[1]青海大学医学院,青海省高原医学应用基础重点实验室,青海西宁810001

出　　处：《中国病理生理杂志》2018年第9期1546-1551,共6页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目(No.81560301;No.81160012);青海省科技厅资助项目(No.2017-ZJ-905)。

摘　　要：目的:探讨不同β-肾上腺素能受体(β-adrenergic receptor,β-AR)在急性低氧应激中对大鼠左、右心室舒缩功能的影响。方法:健康雄性SD大鼠随机分为4组(n=7):对照组(control group)、非选择性β-肾上腺素能受体阻断剂普萘洛尔组(propranolol group)、选择性β_1-肾上腺素能受体阻断剂阿替洛尔组(atenolol group)和选择性β2-肾上腺素能受体阻断剂ICI 118,551组(ICI 118,551 group),各组大鼠分别在常氧(西宁,海拔2 260 m,20.9% O_2,79.1% N_2)和急性低氧(15.0% O_2,85.0% N_2)通气的状态下进行实验,监测各组大鼠心率(heart rate,HR)、左心室收缩压(left ventricular systolic pressure,LVSP)、右心室收缩压(right ventricular systolic pressure,RVSP)及左、右心室内压最大上升和下降速率(±dp/dt_(max))等心功能指标变化;同时,比较低氧通气前后动脉血气的变化。结果:常氧下,propranolol组、atenolol组与ICI 118,551组LVSP和左心室±dp/dt_(max)较给药前降低,同时propranolol组与atenolol组RVSP和右心室±dp/dt_(max)较给药前明显降低(P<0.05)。低氧通气5 min后,各组大鼠与常氧组相比动脉血氧分压(PaO_2)、LVSP和左心室±dp/dt_(max)均降低(P<0.05);但右心室±dp/dt_(max)明显升高(P<0.05);且低氧条件下control组心功能指标的变化程度均比propranolol组和atenolol组明显。结论:低氧应激时心脏β_1-AR的激活可能是心脏发挥代偿调节的重要方式,但右心室通过紧张源性扩张代偿表现出的右心舒缩功能增强对低氧下机体循环血流量的维持更为重要。AIM:To explore the effects of differentβ-adrenergic receptors(β-AR)on the left and right ventricular systolic and diastolic functions in rats under acute hypoxic stress.METHODS:The healthy male SD rats were randomly divided into 4 groups(n=7):control group,non-selectedβ-AR blocker propranolol group,selectedβ1-AR blocker atenolol group and selectedβ2-AR blocker ICI 118,551 group,and then the rats were exposed to normoxia(20.9%O 2,79.1%N 2)and hypoxia(15.0%O 2,85.0%N 2)condition respectively at the altitude of 2 260 m(Xining,China).The heart rate(HR),the left ventricular systolic pressure(LVSP),the right ventricular systolic pressure(RVSP),and the maximum raise/decline rate of left and right ventricular pressure(±d p/d t max)were monitored,and the arterial blood gas in normoxia and hypoxia condition were compared to explore the effect ofβ-AR on the left and right ventricular systolic and diastolic functions in acute hypoxic stress rats.RESULTS:Under normoxia condition,the LVSP,±d p/d t max of left ventricular were decreased in propranolol group,atenolol group and ICI 118,551 group,the RVSP and±d p/d t max of right ventricle were decreased in propranolol group and atenolol group(P<0.05).Under hypoxia condition,the PaO 2,LVSP,±d p/d t max of left ventricle were decreased in all groups compared with the normoxia group,and the±d p/d t max of right ventricle was increased in all groups(P<0.05),also the degree of index change in control group was more obvious than that in propranolol group and atenolol group.CONCLUSION:The activation ofβ1-AR is an important compensatory regulation for heart function during hypoxic stress.However,the compensatory enhancement of right heart function under acute hypoxia condition which through tonogenic dilation is more significant for maintaining the normal circulating blood flow.

关 键 词：Β-肾上腺素能受体 低氧 应激 心脏舒缩功能 代偿 

分 类 号：R135.6[医药卫生—劳动卫生] R363.2[医药卫生—公共卫生与预防医学]