Effects of adenosine agonist R-phenylisopropyl-adenosine on halothane anesthesia and antinociception in rats  

作　　者：Hai-chunMA Yan-fenWANG Chun-shengFENG HuaZHAO ShujiDOHI 

机构地区：[1]DepartmentofAnesthesiology,theFirstHospitalofJilinUniversity,Changchun130021,China//DepartmentofPhysiology,BasicMedicalSchool,JilinUniversity,Changchun130021,Chinan [2]DepartmentofDigestiveDisease,theSecondHospitalofJilinUniversity,Changchun130041,China [3]DepartmentofAnesthesiology,theFirstHospitalofJilinUniversity,Changchun130021,China [4]DepartmentofPhysiology,BasicMedicalSchool,JilinUniversity,Changchun130021,China [5]DepartmentofAnesthesiology,SchoolofMedicine,GifuUniversity,Gifu5008705,Japan

出　　处：《Acta Pharmacologica Sinica》2005年第2期181-185,共5页中国药理学报（英文版）

基　　金：Project supported by Young Teacher Research Grants from Jilin University and by Sciences and Technology Commission of Changchun(№ 0317009)

摘　　要：Aim:To investigate the antinociceptive effect of adenosine agonist R- phenylisopropyl-adenosine(R-PIA)given to conscious rats by intracerebro- ventricular(ICV)and intrathecal(IT),and identify the effect of R-PIA on minimum alveolar concentration(MAC)of halothane with pretreatment of A_1 receptor an- tagonist 8-cyclopentyl-1,3-dipropylxanthine(DPCPX)or K^+ channel blocker 4-aminopyridine(4-AP).Methods:Sprague-Dawley rats were implanted with 24- gauge stainless steel guide cannula using stereotaxic apparatus and ICV method, and an IT catheter(PE-10,8.5cm)was inserted into the lumbar subarachnoid space,while the rats were under pentobarbital anesthesia.After one week of recovery from surgery,rats were randomly assigned to one of the following protocols:MAC of halothane,or tail-flick latency.All measurements were per- formed after R-PIA(0.8-2.0μg)microinjection into ICV and IT with or without pretreatment of DPCPX or 4-AP.Results:Microinjection of adenosine agonist R- PIA in doses of 0.8-2.0μg into ICV and IT produced a significant dose-and time- dependent antinociceptive action as reflected by increasing latency times and ICV administration of adenosine agonist R-PIA(0.8μg)reducing halothane anes- thetic requirements(by 29%).The antinociception and reducing halothane re- quirements effected by adenosine agonist R-PIA was abolished by DPCPX and 4-AP.Conclusion:ICV and IT administration of adenosine agonist R-PIA pro- duced an antinociceptive effect in a dose-dependent manner and decreased hal- othane MAC with painful stimulation through activation of A_1 receptor subtype, and the underlying mechanism involves K^+ channel activation.Aim:To investigate the antinociceptive effect of adenosine agonist R- phenylisopropyl-adenosine(R-PIA)given to conscious rats by intracerebro- ventricular(ICV)and intrathecal(IT),and identify the effect of R-PIA on minimum alveolar concentration(MAC)of halothane with pretreatment of A_1 receptor an- tagonist 8-cyclopentyl-1,3-dipropylxanthine(DPCPX)or K^+ channel blocker 4-aminopyridine(4-AP).Methods:Sprague-Dawley rats were implanted with 24- gauge stainless steel guide cannula using stereotaxic apparatus and ICV method, and an IT catheter(PE-10,8.5cm)was inserted into the lumbar subarachnoid space,while the rats were under pentobarbital anesthesia.After one week of recovery from surgery,rats were randomly assigned to one of the following protocols:MAC of halothane,or tail-flick latency.All measurements were per- formed after R-PIA(0.8-2.0μg)microinjection into ICV and IT with or without pretreatment of DPCPX or 4-AP.Results:Microinjection of adenosine agonist R- PIA in doses of 0.8-2.0μg into ICV and IT produced a significant dose-and time- dependent antinociceptive action as reflected by increasing latency times and ICV administration of adenosine agonist R-PIA(0.8μg)reducing halothane anes- thetic requirements(by 29%).The antinociception and reducing halothane re- quirements effected by adenosine agonist R-PIA was abolished by DPCPX and 4-AP.Conclusion:ICV and IT administration of adenosine agonist R-PIA pro- duced an antinociceptive effect in a dose-dependent manner and decreased hal- othane MAC with painful stimulation through activation of A_1 receptor subtype, and the underlying mechanism involves K^+ channel activation.

关 键 词：ADENOSINE inhalation anesthesia ANALGESIA potassium channels subarachnoid space cerebral ventricles 

分 类 号：R742[医药卫生—神经病学与精神病学] R971[医药卫生—临床医学]