心跳骤停期间及心肺复苏前后前脑M受体变化的实验研究

目的 探讨心跳聚停（ＣＡ）期间及心肺复苏（ＣＰＲ）前后前脑Ｍ受体变化的规律。方法 采用窒息致大鼠ＣＡ的动物模型，５５只Ｗｉｓｔａｒ大鼠随发为正常对照组（ｎ＝８）、手术对照组（ｎ＝７）、ＣＡ１组（ｎ＝８）；窒息１０ｍｉｎ，ＣＡ２组（ｎ＝８）；窒息３０ｍｉｎ，以及ＣＰＲ前组（ｎ＝８）；窒息１０ｍｉｎ和ＣＰＲ后组（ｎ＝９）：窒息１０ｍｉｎ后复苏，自主循环恢复后继续机械通气３０ｍｉｎ，实验结束时断头取脑，

Changes of muscarinic acetylcholine receptor during the asphyxiation-induced cardiac arrest and cardiopulmonary resuscitation in rat forebrain

Objective To investigate the changes of muscarinic acetylcholine receptor(MAChR) during cardiac arrest (CA) and cardiopulmonary resuscitation(CPR) Methods The animal model of CA was established by clamping endotracheal tube at the end expiration Fifty five Wistar rats were randomly divided into 6 groups: normal control group (NC,n=8), sham operated group (SO,n=7) and CA1 group(n=8): 10 min asphyxiation, CA2 group(n=8):20 min asphyxiation ,CA3 group(n=8):30 min asphyxiation, pre CPR group (n=8):10 min asphyxiation and post CPR group: 30 min ventilation after resuscitation following 10 min asphyxiation At the end of experiment the rats were decapitated to detect maximum binding capacity (Bmax) and K D value of MAChR in forebrain using radioligand receptor binding assay Results The animal model of asphyxiation induced CA could be established in 5 min As compared with those in NC group, Bmax increased significantly (P<0 01),but K D value was kept stable in CA3 group(P>0 05) ; Bmax and K D value remained unchanged markedly in the groups of SO,CA1 and CA2 (P>0 05) In comparison with those in pre CPR group,Bmax changed unsignificantly (P>0 05), but K D value significantly increased (P<0 01) in post CPR group Conclusions MAChR density in forebrain increases ,but the affinity dose not change 25 min following asphyxiation induced CA ,indicating that administration of MAChR antagonist may be beneficial for CPR After CPR,the affinity of MAChR to antagonist in forebrain decreases, suggesting that MAChR antagonist , if required, should be administered at the higher dosage