Role of calcitonin gene related peptide,ATP sensitive potassium channel and spinal nerve in the protective effects of intrathecal morphine preconditioning against myocardial postischemia injury in rats / 中国药理学通报

ABSTRACT

Aim To investigate the role of calcitonin gene related peptide(CGRP),ATP sensitive potassium channel(KATP)and spinal nerve in the protective effect of intrathecal morphine preconditioning against myocardial postischemia injury in rats.Methods Rats were established intrathecal catheter placement and myocardial ischemia reperfusion models were randomly assigned to 10 groupscontrol group(CON);intravenous dimethylsulfoxide group(DMSO);intravenous CGRP8-37 group(CGRP8-37,a selective CGRP receptor antagonist,3 nmol?kg~-1);intravenous glibenclamide group(GLI,a non-selective KATP channel inhibitor,0.3 mg?kg~-1);intrathecal 10 ?l of 1% lidocaine group(LID);intrathecal 3?1 ?g?kg~-1 morphine preconditioning group(MPC);intravenous 3 nmol?kg~-1 CGRP8-37+MPC group(CGRP8-37+MPC);intravenous 0.3 mg?kg~-1 GLI+MPC group(GLI+MPC);intravenous 0.3 mg?kg~-1 GLI+LID group(GLI+LID).Indicators to be observed were MAP,HR and RPP(MAP?HR),the volume of area at risk(AAR)and infarct size(IS),and the area of myocardial infarction,which was demonstrated by IS/AAR.Results Compared to CON group,the volume of IS and IS/AAR was reduced in MPC,LID,LID+MPC and GLI+LID group(P