Effects Of Combined α₂-adrenergic Receptor Agonist And κ-opioid Receptor Agonist On Postresuscitation Cardiac Function In Rabbits

Objective:Postresuscitation myocardial dysfunction contributes to the high fatality rate following successful resuscitation.The purpose of this animal research to investigate the effects of combinedα₂-adrenergic receptor agonist andκ-opioid receptor agonist on cardiac function in rabbits,and to explore if they can improve postresuscitation myocardial dysfunction.Methods:Ventricular fibrillation(VF) was induced by the external electricity,After setting up cardiopulmonary resuscitation model in rabbits,30 rabbits were randomly divided into 5 groups,namely,epinephrine group(E),vasopressin group(V),U50488H group (U),mivazerol group(M),mivazerol+U50488H group(M+U),medicines were administered respectively during CPR.Hemodynamics,B-type natriuretic peptide and myocardial injury marker cardiac troponin T were examined before VF and the early stage of postresuscitation(30-240min),Animals were killed after experiment ended,The left ventricules of the rabbits were obtained for light microscopic observation.Results:(1)MAP,peak-dp/dt and peak+dp/dt in M+U group were significantly higher than any other groups,and the increase of LVEDP was less than other groups(P＜0.05). (2)The serum concentrations of BNP in M+U group significantly decreased than those in any other groups(P＜0.01 vs E,V,U,P＜0.05vs M).(3)The concentration of cTnT in M+U group significantly decreased than those in any other groups(P＜0.01 vs E,V, P＜0.05 vs M,U).(4) Myocardium damages are shown from heavy to light under light microscopic observation:E,V＞M＞U＞M+U.Conclusion:Combinedα₂-adrenergic receptor agonist(mivazerol) andκ-opioid receptor agonist(U50488H) can improve postresuscitation hemodynamics and reduce the concentration of B-type natriuretic peptide and cardiac troponin T in the early stage of postresuscitation and alleviate myocardial damage in pathological,and improve postresuscitation myocardial dysfunction.