發(fā)布時(shí)間：2018-04-05 11:10

  本文選題：勞力性熱射病　切入點(diǎn)：熱應(yīng)激反應(yīng)　出處：《第二軍醫(yī)大學(xué)》2016年博士論文

【摘要】：勞力性熱射病(Exertional Heat Stroke,EHS)是在高溫高濕環(huán)境下強(qiáng)體力訓(xùn)練、施工時(shí)發(fā)生的嚴(yán)重中暑,表現(xiàn)為高熱、昏迷、抽搐、橫紋肌溶解,多并發(fā)多臟器功能衰竭,如果延誤治療,該病的致死率高達(dá)50-70%以上。勞力性熱射病的發(fā)生除了高溫傷害以外,還與長時(shí)間的高強(qiáng)度體能運(yùn)動(dòng)導(dǎo)致機(jī)體重要臟器相對缺血、缺氧有關(guān)。無論高溫還是缺氧都將損害線粒體功能,加劇機(jī)體的缺氧,使病情進(jìn)一步惡化。及時(shí)保護(hù)線粒體功能有助于減輕EHS對機(jī)體的傷害。線粒體作為機(jī)體有氧呼吸和氧化磷酸化產(chǎn)能的細(xì)胞器。當(dāng)全身出現(xiàn)急性缺血缺氧性損傷時(shí),線粒體的結(jié)構(gòu)和功能也有可能損害。大株紅景天的主要成分為紅景天苷,能夠抑制缺氧、低糖致傷的線粒體損傷,減少細(xì)胞凋亡的發(fā)生,已被廣泛應(yīng)用于改善心肌急慢性缺氧、缺血性損傷。因此在理論上復(fù)合兩種損傷的勞力性熱射病一定會(huì)出現(xiàn)線粒體結(jié)構(gòu)和功能的損害,造成后續(xù)組織器官能量代謝障礙。這或許是勞力性熱射病時(shí)出現(xiàn)一系列病理生理改變的關(guān)鍵環(huán)節(jié)之一。因此本課題擬分析勞力性熱射病時(shí)機(jī)體組織細(xì)胞線粒體損傷特點(diǎn)以及探討紅景天苷對線粒體的保護(hù)作用。本課題以勞力性熱射病大鼠模型為研究對像,比較分析不同條件下各組大鼠線粒體相關(guān)指標(biāo)的檢測結(jié)果,獲得相關(guān)環(huán)境參數(shù)以及模型動(dòng)物的臨床表現(xiàn)和各檢測指標(biāo)的變化,得到勞力性熱射病線粒體結(jié)構(gòu)、功能損傷特點(diǎn)及分子機(jī)制;并進(jìn)一步利用勞力性熱射病大鼠模型,比較分析勞力性熱射病大鼠和紅景天苷不同劑量組大鼠的各相關(guān)檢測指標(biāo),探索紅景天苷對勞力性熱射病線粒體結(jié)構(gòu)、功能損傷的保護(hù)作用及其可能的機(jī)制。第一部分勞力性熱射病大鼠動(dòng)物模型及線粒體損傷特點(diǎn)目的:建立穩(wěn)定的勞力性熱射病大鼠動(dòng)物模型,并研究線粒體結(jié)構(gòu)、功能損害特點(diǎn)。方法:40只SD大鼠,隨機(jī)分4組,每組10只:(A)對照組、(B)常溫力竭組、(C)高溫組,即非勞力性熱射病組、(D)勞力性熱射病組。其中A組大鼠常規(guī)方法飼養(yǎng);B組大鼠在溫度22℃飼養(yǎng),迫使其在實(shí)驗(yàn)動(dòng)物跑臺(tái)進(jìn)行跑步運(yùn)動(dòng)(速度恒定為15m/min)。當(dāng)大鼠停下是即給予電擊(電壓100V),直到大鼠力竭。C組大鼠放置于溫度45℃條件下,不迫使大鼠運(yùn)動(dòng),直到大鼠出現(xiàn)熱射病表現(xiàn)。D組大鼠在溫度45℃,濕度70%±5%的環(huán)境下給予同B組同樣的運(yùn)動(dòng)處理方式。結(jié)合對照組,對比分析各組的線粒體結(jié)構(gòu)和功能損傷的特點(diǎn),包括線粒體膜電位(MMP),呼吸控制率(RCR),氧自由基(ROS),Ca2+,戊二醛(MDA)和超氧化物歧化酶(SOD)活性和PGC-1αm RNA以及Mn SOD m RNA等的變化情況。結(jié)果:1.在環(huán)境溫度45℃,濕度70%±5%條件下,給予15m/min速度持續(xù)奔跑,可以構(gòu)建勞力性熱射病大鼠模型。2.電鏡顯示勞力性熱射病組大鼠心、肝細(xì)胞和線粒體損傷表現(xiàn)為心肌和肝臟細(xì)胞顯著腫脹,細(xì)胞膜碎裂,細(xì)胞器散落,線粒體表現(xiàn)為腫脹,甚至出現(xiàn)空泡改變,內(nèi)部基質(zhì)密度不均勻,內(nèi)腔明顯擴(kuò)張,嵴斷裂。3.勞力性熱射病大鼠心、肝線粒體膜電位、呼吸控制率、離子鈣濃度、SOD濃度顯著低于對照組(0.05),ROS和MDA顯著高于對照組(0.05),(PGC-lα)m RNA以及Mn SOD m RNA表達(dá)低于對照組。結(jié)論:勞力性熱射病時(shí)細(xì)胞與線粒體結(jié)構(gòu)首先受損,并出現(xiàn)膜電位、呼吸控制率、離子鈣、SOD下降,氧自由基蓄積,MDA升高和(PGC-lα)m RNA以及Mn SOD m RNA表達(dá)下降等功能損傷。第二部分紅景天苷對勞力性熱射病大鼠線粒體的保護(hù)作用目的:探討紅景天苷對勞力性熱射病大鼠線粒體的保護(hù)作用機(jī)制。方法:50只SD大鼠隨機(jī)分為5組,分別為常溫飼養(yǎng)紅景天苷組(A組)、常規(guī)飼養(yǎng)勞力性熱射病組(B組)、紅景天苷低劑量組(L,4 mg/kg,C組)、中劑量組(M,10mg/kg,D組)、高劑量組(H,25 mg/kg,E組)。B、C、D、E組的勞力性熱射病動(dòng)物模型參照第一部分介紹的方法構(gòu)建。對比分析不同劑量紅景天苷飼養(yǎng)的勞力性熱射病組大鼠與其余2組的運(yùn)動(dòng)距離、時(shí)間以及線粒體結(jié)構(gòu)與功能指標(biāo),包括粒體膜電位(MMP),呼吸控制率(RCR),氧自由基(ROS),Ca2+,戊二醛(MDA)和超氧化物歧化酶(SOD)活性和PGC-1αm RNA以及Mn SOD m RNA表達(dá)水平。結(jié)果:高劑量紅景天苷組的勞力性熱射病大鼠線粒體結(jié)構(gòu)與功能損傷程度低于常規(guī)飼養(yǎng)勞力性熱射病組。表現(xiàn)為線粒體膜電位、呼吸控制率、離子鈣濃度、SOD濃度顯著高于常規(guī)飼養(yǎng)勞力性熱射病組大鼠。ROS和MDA顯著低于對照組,PGC-lαm RNA以及Mn SOD m RNA表達(dá)高于對照組。結(jié)論:高劑量的紅景天苷通過穩(wěn)定勞力性熱射病大鼠線粒體的膜電位、呼吸控制率、離子鈣濃度、SOD濃度并清除ROS和MDA并通過提高PGC-lαm RNA以及Mn SOD m RNA表達(dá)水平發(fā)揮保護(hù)作用。
[Abstract]:Exertional heat stroke (Exertional Heat, Stroke, EHS) is a strong physical training in high temperature and high humidity environment, severe heat stroke occurred during the construction of the performance for the high fever, coma, convulsions, rhabdomyolysis, more complicated with multiple organ failure, if the delay in treatment, the disease mortality rate as high as 50-70% exertional above. Heat stroke in addition to the occurrence of high temperature damage, and high intensity of physical exercise for a long time due to the important organs relative ischemia, hypoxia or hypoxia. Both high temperature will damage the function of mitochondria, increased body hypoxia, which worsens the situation. Timely protection of mitochondrial function is helpful to reduce the damage to the body. Mitochondrial EHS as the body cell respiration and oxidative phosphorylation capacity. When the body in the acute hypoxic ischemic injury, the structure and function of mitochondria may also damage. The main component of the large red Sedum plant As salidroside can inhibit hypoxia, mitochondrial damage, low sugar injury, apoptosis, has been widely used in acute and chronic hypoxic ischemic myocardial injury. Therefore, exertional heat stroke in the composite theory of two kinds of damage will appear to impair mitochondrial structure and function, causing the subsequent organization organ of energy metabolism disorder. This is probably one of the key links in a series of pathophysiological changes in the emergence of exertional heat stroke. Therefore this paper analysis of exertional heat stroke when the body tissue mitochondrial damage characteristics and to investigate the protective effect of red Sedum glycosides on mitochondria. The model of exertional heat stroke in rats in order to study the like, comparative analysis of results in detection of mitochondrial related indicators of rats under different conditions, obtain the relevant environmental parameters and animal models and clinical manifestations of all parameters change And get the exertional heat stroke mitochondrial structure, functional characteristics and molecular mechanism of injury; and further use of exertional heat stroke rat model, comparative analysis of exertional heat stroke rats and Salidroside in different dose group rats all relevant indexes, to explore the effect of salidroside on exertional heat stroke mitochondrial structure, protection function injury and its possible mechanism. The first part of exertional heat stroke rat animal model and the characteristics of Mitochondrial Injury Objective: to establish a rat animal model of stable exertional heat stroke, and to study the mitochondrial structure, function characteristics. Methods: 40 SD rats were randomly divided into 4 groups, each group 10: (A) control group, (B) at contrastingexhaustion group (C), the high temperature group, namely non exertional heat stroke group (D), exertional heat stroke group. The rats in the A group of conventional breeding methods; the rats in group B at a temperature of 22 DEG C 027, forcing it to in the experimental animal ran into Taiwan 琛岃窇姝ヨ繍鍔，

本文編號(hào)：1714507