牛磺酸对严重烧伤大鼠心肌损害的保护作用

目的　观察牛磺酸(Tau)对严重烧伤大鼠心肌损害的作用。　方法　将Wistar大鼠随机分为对照组(10只,不致伤)、烧伤组(60只)和Tau治疗组(60只)。后两组大鼠造成30%TBSAⅢ度烫伤(以下称烧伤),烧伤组伤后常规补液,Tau治疗组伤后腹腔注射Tau400mg/kg.于两组烧伤大鼠伤后1、3、6、12、24、48h检测其血浆中心肌肌钙蛋白T(cTnT)、丙二醛(MDA)的含量以及血浆、心肌组织中肿瘤坏死因子α(TNF- α)、血管紧张素Ⅱ(AngⅡ)的含量、心肌钙离子水平,用透射电镜观察心肌组织形态结构变化,并与对照组的上述指标进行比较。将烧伤组大鼠血浆TNF- α、AngⅡ检测结果分别与cTnT检测结果作相关性分析。　结果　烧伤组大鼠伤后3h起血浆cTnT水平较对照组(0.16±0. 03)μg/L显著升高(P<0. 01), 12h达峰值(6. 32±0. 41)μg/L, 48h仍显著高于对照组(P<0. 01).烧伤组伤后3—48h血浆MDA含量及心肌钙离子水平明显高于对照组(P<0. 01 );伤后6—48h血浆和心肌组织TNF- α含量显著高于对照组(P<0. 01);血浆及心肌组织中AngⅡ水平分别于伤后1—24h、3—24h明显高于对照组(P<0. 01).Tau治疗组上述指标在伤后多数时相点明显低于烧伤组(P<0. 01). 烧伤组大鼠伤后早期心肌肌丝断裂溶解、线粒体肿胀、嵴减少,Tau治疗组心肌组织接近正常。烧伤组

Protective effects of taurine on myocardial injury in severely burned rats

OBJECTIVE: To investigate the effect of taurine on myocardial injury in severely scalded rats. METHODS: A total of 130 healthy adult Wistar rats were randomly divided into 3 groups: the control group (C, without burns), the burn group (B, subjected to a 30% TBSA III degree scalding) and the treatment group (T, treated with intraperitoneal injection of taurine (400 mg/kg) immediately after scald injury). The plasma and myocardial tissue samples in B and T groups were harvested at 1, 3, 6, 12, 24 and 48 postburn hours (PBH) for the determination of the contents of cardiac troponin T (cTnT), malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-alpha), and angiotensin II (AngII) in plasma, and the contents of TNF-alpha, AngII and calciumion in myocardial tissue. The morphological change in the myocardial tissue was observed with transmission electronic microscope (TEM) and was compared with that in C group. The changes in the plasma TNF-alpha and AngII were analyzed in relation to that of plasma cTnT. RESULTS: The plasma cTnT content in B group at 3 PBH was markedly higher than that in C group (0.16 +/- 0.03 microg/L) (P < 0.01), and it peaked (6.32 +/- 0.41) at 12 PBH and remained at high level at 48 PBH. While the plasma MDA content and the calciumion level in B group were evidently higher than those in C group during 3 to 48 PBH (P < 0.01). The TNF-alpha contents in plasma and myocardial tissue during 6 to 48 PBH were significantly higher than those in C group (P < 0.01). The AngII contents in plasma and myocardial tissue during 3 to 24 PBH were obviously higher than those in C group (P < 0.01). All the indices in T group were significantly lower than those in B group (P < 0.01). Histological examination revealed that there was myocardial damage in various degrees during early postburn stage in B group, such as focal dissolution and fragmentation of myofilament, mitochondrial edema, myocyte sarcoplasmic protrusions like piano keys. But all the above changes in T group were evidently ameliorated to near normal. There was close positive correlation between the change in the concentrations of plasma content of TNF-alpha and AngII and cTnT in B group (r = 0.87 and 0.82, P < 0.05). CONCLUSION: The production of TNF-alpha, MDA, cTnT, AngII and high calicumion level of myocardiocytes in severely burned rats can be inhibited by taurine, which was beneficial in the management of myocardial injury after severe burns.