丙戊酸钠对严重烫伤合并海水浸泡延迟补液模型大鼠心脑损伤的保护作用

Protective effects of valproic acid on cardiac and cerebral injury in rats subjected to severe scalding combined with seawater immersion injury with delayed fluid replacement

目的研究丙戊酸钠对严重烫伤合并海水浸泡延迟补液模型大鼠心脑损伤的保护作用。方法将大鼠按照随机数字表法分为烫伤+延迟补液组(S组)、烫伤+海水浸泡+延迟补液组(SS组)、烫伤+海水浸泡+丙戊酸钠+延迟补液组(SSV组),每组60只。所有大鼠采用沸水水浴法建立35%总体表面积Ⅲ度烫伤模型。SS组和SSV组大鼠烫伤后立即浸泡于人工海水中(30 min),其中SSV组出水后即刻皮下注射丙戊酸钠300 mg/kg。各组烫伤后2 h按1/2 Parkland公式于30 min内静脉输入乳酸钠林格注射液进行延迟补液。记录大鼠死亡时间,计算各组大鼠平均生存时间和24 h生存率;分别于烫伤前和烫伤后0、2、5 h检测大鼠的平均动脉压(MAP)、心率(HR)、呼吸频率(RR)、直肠温度(RT)、动脉血pH、动脉血氧分压(Pa O_(2))、动脉血二氧化碳分压(PaCO_(2))、实际碳酸氢根(HCO3-)、肌酸激酶同工酶(CK-MB)、神经元烯醇化酶(NSE);观察大鼠心脏、脑组织病理变化。结果SS组大鼠24 h生存率(55%)较S组(90%)显著降低,而SSV组大鼠24 h生存率(75%)较SS组显著升高(P<0.05);与S组比较,SS组大鼠烫伤后0、2、5h的MAP、RT、HR、pH、Pa O_(2)、HCO3-显著降低而CK-MB、NSE水平显著升高,烫伤后2、5 h的PaCO_(2)显著升高,烫伤后0、2 h的RR显著降低(P<0.05);与SS组比较,SSV组大鼠在烫伤后2、5 h的MAP、RT、HR、pH、Pa O_(2)、HCO3-显著升高而PaCO_(2)和CK-MB、NSE水平显著降低,烫伤后2 h的RR显著升高(P<0.05)。在烫伤后2、5 h,SS组大鼠心脏、脑组织损伤程度较S组明显加重;SSV组大鼠心脏、脑组织病理损伤程度较SS组明显减轻。结论严重烫伤大鼠合并海水浸泡后,皮下注射丙戊酸钠能保护大鼠心脑功能,改善生命体征和血气指标,延长其存活时间,提高其生存率。

OBJECTIVE To study the protective effects of valproic acid on cardiac and cerebral injury in rats subjected to severe scalding combined with seawater immersion injury with delayed fluid replacement.METHODS The rats were divided into scalding+delayed fluid replacement group(group S),scalding+seawater immersion+delayed fluid replacement group(group SS),scalding+seawater immersion+valproic acid+delayed fluid replacement group(group SSV)according to random number table,with60 rats in each group.All groups were subjected to 35%total body surface area third-degree full-thickness scalding with boiled water.Group SS and group SSV were immersed in artificial seawater(30 min)immediately after scalding,and group SSV was subcutaneously injected with valproic acid 300 mg/kg immediately after out of water.Sodium lactate Ringer’s injection was injected intravenously within 30 minutes according to 1/2 Parkland formula at 2 h after scalding in each group for delayed fluid replacement.The death time of rats was recorded,and the average survival time and 24 h survival rate of rats in each group were calculated.Mean arterial pressure(MAP),heart rate(HR),respiration rate(RR),rectal temperature(RT),arterial blood p H,arterial partial pressure of oxygen(Pa O_(2)),arterial blood partial pressure of carbon dioxide(Pa CO_(2)),HCO3-,creatine kinase MB isoenzyme(CK-MB)and neuron specific enolase(NSE)were detected before scalding,at 0,2,5 h after scalding.The pathological changes of cardiac and cerebral tissue were observed.RESULTS The 24 h survival rate of group SS(55%)was significantly lower than that of group S(90%),while that of group SSV(75%)was increased significantly,compared with group SS(P<0.05).Compared with group S,the levels of MAP,RT,HR,p H,Pa O_(2)and HCO3-in group SS were significantly lowered,while the levels of CK-MB and NSE were increased significantly at 0,2,5 h after scalding;the levels of Pa CO_(2)were increased significantly at 2,5 h after scalding,while the levels of RR were decreased significantly at 0,2 h after scalding(P<0.05).Compared with group SS,the levels of MAP,RT,HR,p H,Pa O_(2)and HCO3-in group SSV were significantly increased,while the levels of Pa CO_(2),CK-MB and NSE were decreased significantly at 2,5 h after scalding;the level of RR was increased significantly at 2 h after scalding(P<0.05).At2,5 h after scalding,cardiac and cerebral injury of rats in group SS were aggravated significantly than that in group S;cardiac and cerebral injury of rats in group SSV were relieved significantly than that in group SS.CONCLUSIONS After severe scalding combined seawater immersion injury,hypodermic injection of sodium valproate could protect cardiac and cerebral function of rats,improve vital signs and blood gas index,prolong survival time and improve survival rate in rats.