Effects of Ulinastatin on brain injured and cardiac function compromised after cardiopulmonary resuscitation in rabbits

Abstract

Objective To investigate whether Ulinastatin (UTI) would minimize the systemic inflammatory response,lessen cardiac dysfunction and protect neurons against injury in hippocampus CA1area after restoration of spontaneous circulation (ROSC). Methods Animal models of cardiac arrest were established in 24 New Zealand rabbits,and those animals were randomly (random number) divided into control group and UTI treated group after ROSC.Changes in the levels of plasma inflammatory cytokines TNF-α and IL-6 were assayed before cardiac arrest and 4,8,12 and 16 hours after ROSC.Cardiac function including FS,EF and E/A were observed with ultrasonography before cardiac arrest and 4,8,12 and 16hours after ROSC,and viable and apoptotic neurons in hippocampus CA1 area and infiltrations of MPO positive cells in myocardium,cerebrum,liver,kidney and intestine were counted 72 hours after ROSC.The t-test or Mann-Whitney rank sum test was used to verify the specified theoretical distribution functions of the biomarkers tested by Kolmogorov-Smirnov test,POST HOC test was used for the multiple comparisons,and Pearson correlation analysis was used to investigate the correlation between inflammatory cytokines and cardiac function. Results The levels of TNF-α and IL-6 in UTI group were lower than those in control group as those data got 4,8,12 and 16 hours after ROSC (P ＜0.05).EF and E/A in UTI treated group were higher than those in the control group as those data got 4,8,12 hours after ROSC.FS values obtained 4 h and 8 hours after ROSC were higher in UTI group than those in control group ( P ＜ 0.05 ).The Pearson correlation analysis showed that the levels of TNF-α and IL-6 significantly correlated with EF after ROSC.The number of viable neurons in CA1 area of control group was ( 13.22 ± 0.97) which was lower than that in UTI group ( 16.89 ± 1.45 ) ( P =0.003 ),while the number of apoptotic neurons in hippocampus CA1 area was higher in control group than that in UTI group (15.67 ± 1.37) vs.(13.67 ± 1.03 ) (P =0.019).The numbers of MPO positive cells were significantly lower in liver,kidney and intestine in group UTI than those in control group. Conclusions UTI could inhibit the infiltration of MPO positive cells in liver,kidney and intestine,decreasing the levels of TNF-α and IL-6 in plasma,in turn lessening cardiac dysfunction and protecting neurons from injury in hippocampus CA1 area after ROSC of New Zealand rabbits. Key words: Cardiopulmonary resuscitation; New Zealand rabbit; Ulinastatin; Cardiac dysfunction; Neurons