激活颈动脉体mGluR1抑制慢性间歇性低氧所致大鼠颈动脉体可塑性  

Activation of metabotropic glutamate receptor 1 inhibits chronic intermittent hypoxia-induced carotid body plasticity in rats

作　　者：李超红[1,2] 赵晨露 刘玉珍 LI Chao-Hong;ZHAO Chen-Lu;LIU Yu-Zhen(The First Affiliated Hospital of Xinxiang Medical University,Henan Key Laboratory of Neural Regeneration and Repairment,Life Sciences Research Center,Weihui 453100,China;Department of Cardiology,The Second Affiliated Hospital of Chongqing Medical University,Chongqing 404100,China)

机构地区：[1]新乡医学院第一附属医院,河南省神经修复重点实验室,生命科学研究中心,卫辉453100 [2]重庆医科大学附属第二医院心血管内科,重庆404100

出　　处：《生理学报》2023年第5期629-635,共7页Acta Physiologica Sinica

基　　金：supported by the National Natural Science Foundation of China(No.81973988,81470271);the Henan Provincial Science and Technology Research Project(No.222102310295);the Henan Plan of the Medical Science and Technology Research(No.LHGJ20200499).

摘　　要：本文旨在探讨代谢型谷氨酸受体1(metabotropic glutamate receptor 1,mGluR1)在慢性间歇性低氧(chronic intermittent hypoxia,CIH)所致大鼠颈动脉体可塑性中的作用。对Sprague Dawley(SD)大鼠CIH(6%~21%O2,4 min/循环,8 h/天)处理4周,无创法测量其尾动脉血压。通过RT-qPCR检测颈动脉体mGluR1的mRNA表达水平;Western blot检测颈动脉体mGluR1的蛋白表达水平;通过离体胞外记录技术描记颈动脉体窦神经放电,并给予急性间歇性低氧(5%O21 min间歇95%O25 min,10次)诱导颈动脉体窦神经感觉长时程易化(sensory long-term facilitation,sLTF),观察mGluR1在CIH所致颈动脉体窦神经sLTF中的作用。结果显示:与对照组相比较,CIH处理4周的大鼠收缩压(P<0.001)、舒张压(P<0.005)、平均动脉压(P<0.001)均明显升高。与对照组相比,CIH组大鼠颈动脉体中mGluR1的mRNA及蛋白表达水平均下降(P<0.01)。与对照组大鼠相比,CIH组大鼠可诱导颈动脉体窦神经sLTF;预先应用I组代谢型谷氨酸受体激动剂(S)-3,5-二羟基苯基甘氨酸(DHPG)激活颈动脉体mGluR1则抑制CIH大鼠颈动脉体窦神经sLTF(P<0.005)。上述结果提示,激活颈动脉体mGluR1可抑制CIH所致颈动脉体可塑性。The purpose of the present study was to explore the role of carotid body metabotropic glutamate receptor 1(mGluR1)in chronic intermittent hypoxia(CIH)-induced carotid body plasticity.Sprague Dawley(SD)rats were exposed to CIH(6%–21%O2,4 min/cycle,8 h/day)for 4 weeks.The blood pressure of rats was monitored non-invasively by tail-cuff method under consciousness.RT-qPCR was used to examine the mRNA expression level of mGluR1 in rat carotid body.Western blot was used to detect the protein expression level of mGluR1 in rat carotid body.The role of mGluR1 in CIH-induced carotid body sensory long-term facilitation(sLTF)was investigated by ex vivo carotid sinus nerve discharge recording,and the carotid body sLTF was evoked by a 10-episode of repetitive acute intermittent hypoxia(AIH:1 min of 5%O2 interspersed with 5 min of 95%O2).The results showed that:(1)CIH increased the systolic blood pressure(P<0.001),diastolic blood pressure(P<0.005)and mean arterial blood pressure(P<0.001)of rats;(2)CIH decreased the mRNA and protein levels of mGluR1 in the rat carotid body(P<0.01);(3)4 weeks of CIH induced carotid body sLTF significantly,exhibiting as an increasing baseline sensory activity during post-AIH,which was inhibited by application of an agonist of group I metabotropic glutamate receptors,(S)-3,5-dihydroxyphenylglycine(DHPG),during sLTF induction(P<0.005).In summary,these results suggest that activation of mGluR1 inhibits CIH-induced carotid body plasticity in rats.

关 键 词：代谢型谷氨酸受体1 慢性间歇性低氧 颈动脉体可塑性 

分 类 号：R766[医药卫生—耳鼻咽喉科]