The Effect Of Tea Polyphenols On Survival Time And Renal Injury After Resuscitation In Rats

Objectives:Cardiac arrest (CA) caused by a variety of reasons results in severe anoxia and ischemia in body’s organs. Although timely and effective cardiopulmonary resuscitation (CPR) can bring return of spontaneous circulation (ROSC) in some patients, ischemic reperfusion injury occurs in organs at same time, in turn to impact badly on suvival time and suvival quality after resuscitation. It is one of the most hotspot in medicine at present how to decrease mortality and disability rate after resuscitation. Tea polyphenols has strong antioxidant effect and can protect the heart, brain and kidney in local ischemia reperfusion. CPR and CA cause also ischemic reperfusion injury. If TP can improve CPR outcome via its antioxidant effect?this study evaluates the TP effect on CPR to provide experimental basis for antioxidant treatment on organ functional improvement after resuscitation. TP was used in an asphyxia rat model as soon as ROSC. Hemodynamics. suvival time and nerve function were monitored, renal morphologic alterations were observed, Superoxide Dismutase (SOD) and Malondialdehy de (MDA) of renal tissues were tested.Methods:Sprague-Dawley rats, weighing 200-400g were anesthetized by Chloral Hydrate (3ml/kg> intraperitoneal injection). Asphyxial cardiac arrest was induced by clamping the tracheal tubes. At the end of 8 min of asphyxiation, CPR was started with chest press and mechanical ventilation. Epinephrine (0.04mg/kg) was injected at 1 min of compression. The animals were treated randomly with either saline (2ml/kg) or TP (10mg/kg) following ROSC. The changes of systolic pressure, diastolic pressure, mean arterial pressure were monitored after 1h of ROSC. Survival time, neurological deficit score (NDS) and the survival rate were recorded after 12,24 and 48h of ROSC respectively. The renal conventional sections from 12h,24h,48h survival rats were done to observe pathological changes. SOD, MDA of renal homogenate of these rats were assayed.Results:1.There was no significant difference in systolic pressure, diastolic pressure, mean arterial pressure within 1h of post-resuscitation in the TP group and the saline group. The survival time of rats in TP group was significantly longer than that of in saline group (37.3±11.2h vs 24.3±14.1h, P<0.05),24h and 48h survival rates in TP group after ROSC and NDS score were also significantly higher than that of saline group (P<0.01, P<0.05).2. The morphologic observation indicted that TP alleviated renal structural injury in post-resuscitation rats.There were not significant difference in SOD and MDA of renal homogenate of 24h,48h suvival rats between TP group and saline groupConclusion:1.TP can improve CPR outcome in asphyxial CA rats, presenting the enlongation of survival time, the increase survival rate of 24h and 48h with the improvement of nerve function.2. TP can alleviate renal structural injury in asphyxial CA rats.