实验性睾丸缺血超声表现与再灌注后组织变化相关性研究

目的:探讨不同程度急性单侧睾丸缺血的二维、彩色多普勒(CDU)及超声造影表现与再灌注后睾丸病理变化的相关性。方法:32只大白兔随机分成对照组、缺血组(A、B、C组),每组8只。缺血组在超声监测下制成不同程度的单侧睾丸缺血模型,A组,睾丸回声均匀、血流信号轻度减少;B组,睾丸回声不均匀、血流信号明显减少;C组,睾丸出现放射状或小片状低回声、血流信号消失。各组在出现上述声像图变化后予以再灌注。缺血前及再灌注前分别行双侧睾丸超声造影。1个月后观察各组缺血睾丸病理变化。比对分析各组超声表现与生精功能之间的关系。结果:超声造影:与对照组比较,A、B组缺血睾丸造影参数到达时间、速度、达峰时间、峰值减半时间有显著差异(P<0.05),峰值基础强度差A组无明显差异(P>0.05)、B组有显著差异(P<0.05);C组无造影剂充盈。1个月后缺血睾丸Johnsen评分:与对照组(9.10±0.11)比较,A组(8.70±0.39)无显著差异(P>0.05),B组(6.01±0.88)有显著差异(P<0.05),C组(3.16±1.05)有极显著差异(P<0.01)。结论:与CDU相比,超声造影能较好地反映缺血睾丸组织的血流灌注情况,睾丸缺血的不同超声表现与再灌注后生精功能明显相关,超声检查能对再灌注后睾丸生精功能的预测提供帮助。     

离体睾丸缺血再灌注损伤的实验研究

目的 探讨人离体睾丸缺血再灌注损伤的变化规律。了解益生注射液对其变化的干预效果。方法 采用13人摆脱赠尸睾丸26只,用4℃250ml高渗枸橼酸盐嘌呤液冷保存,再以此液500ml再灌注,实验组用含500μg/ml益生注射液同法操作,同一睾丸于单纯冷保存（对照组睾丸8只,实验组8只）6、12、18、24、36、48、60和72小时连续取材,冷保存6、12、18、24和36小时（对照组与实验组每时间点各1只,共10只）后,37）复温再灌注6和12小时连续取材,作组织学及酶组织化学染色。结果 实验组睾丸组织4℃冷保存24小时内无明显病理改变;36和48小时后出现精索血管内皮细胞肿胀,变性及部分脱落,曲细精管与生精上皮剥离,间质轻度水肿等损伤;冷保存12小时乳酸脱氢酶与琥珀酸脱氢酶活性增高,24小时后又降低;一氧化氮合成酶活性于冷保存18小时后降低再灌注后组织损伤加重,对照组睾丸单纯冷保存12小时即出现精索血管内皮细胞肿胀,变性,24小时后加重,再灌注后精索血管大量内皮细胞变性脱落,曲细精管基膜剥离和间质水肿严重。结论 4℃冷保存24小时内仅有内皮细胞轻微损伤,超过24小时可引起睾丸血管及组织形态结构明显异常,37℃复温再灌注使损伤程度加重,益生注射液使人离体睾丸在4℃冷保存24小时内保持正常形态结构。且对再灌注损伤有保护作用。     

离体人睾丸缺血再灌注损伤模型

目的：建立离体人睾丸的缺备再灌注（I／R）损伤模型，为研究抗I／R损伤药物的作用及机理提供一实质器官灌注模型。方法：采用１３例捐赠尸睾，用250ml0℃-4℃高渗枸橼酸盐嘌呤液灌洗后冷存，再以500ml37℃该液进行再灌注，不同时间点取材作组织学及酶组织化学检查。结果：4℃冷缺血12h开始出现血管仙皮细胞肿胀、变圆、空泡样变，24h内皮细胞变性脱落，睾丸曲细精管基膜与生精上皮剥离，生精细胞变性脱落，间质水肿等，病变随冷缺血时间延长而加重。酶组化结果显示，单纯冷保存18h后，睾丸组织乳酸脱氢酶（LDH）活性升高，琥珀酸脱氢酶（SDH）活性24h后升高，经37℃复温再灌注后损伤明显加重。结论：离体人睾丸可替代人体其它实质器官作为研究I／R损伤的离体灌注模型。     

药物和缺血预处理对肝硬化肝脏缺血再灌注损伤的协同保护作用

目的探讨阿霉素和缺血联合预处理对肝硬化肝脏缺血再灌注损伤的保护作用及其可能机制方法(1)诱导大鼠肝硬化模型；(2)缺血再灌注损伤前3组肝硬化大鼠分别行阿霉素预处理、缺血预处理、阿霉素 缺血联合预处理，比较3组和对照组AST、ALT、LDH和盯、TNF-α、NO、热休克蛋白70(HSP0)差异有显著性。结果阿霉素预处理、缺血预处理、阿霉素 缺血联合预处理能明显抑制AST、ALT、LDH水平升高，其中以阿霉素 缺血联合预处理作用最显著；缺血预处理能显著降低ET、TNF-α水平；阿霉素预处理和缺血预处理使N0显著升高；阿霉素预处理能使肝细胞HSP70显著增加。结论阿霉素和缺血预处理都能减轻肝硬化肝脏缺血再灌注损伤程度；阿霉素 缺血联合预处理对月十硬化肝脏缺血再灌注损伤有协同保护作用。     

预缺血对肝脏缺血再灌注损伤的保护作用

已有较多的实验证明,预缺血处理对多种缺血再灌注器官有保护作用.本文综述了预缺血对缺血再灌注肝脏的保护作用及其机理.     

缺血后处理对兔睾丸缺血再灌注的影响

目的:探讨缺血后处理对不同缺血程度的兔睾丸缺血再灌注损伤的作用。方法:42只雄性大白兔随机分成对照组、缺血组(R1、R2、R3组)、后处理组(P1、P2、P3组),每组6只。缺血组、后处理组在超声监测下制成睾丸不同缺血程度模型:R1、P1组睾丸回声均匀,血流轻度减少;R2、P2组睾丸回声增粗,血流明显减少;R3、P3组睾丸出现片状或放射状低回声,血流信号消失。出现上述图像变化后,缺血组给予直接灌流,后处理组于恢复灌流前给予后处理措施,即再灌注30s/缺血30s,反复3次。再灌注前进行超声造影,3d后测定各组组织丙二醛(MDA)、超氧化物歧化酶(SOD)含量。HE染色后光镜下观察睾丸组织和病理学改变,并行Johnsen's评分和凋亡指数分析;电镜下观察睾丸组织超微结构。结果:再灌注前各造影参数速度参数(β)、峰值时间(TTP)、峰值基础强度差(PBD)、峰值减半时间(DT/2),R1与P1组比较均无显著差异(P>0.05)、R2与P2组比较均无显著差异(P>0.05)、R3与P3组无显影。MDA含量:R1与P1组比较有显著差异(P<0.05),R2与P2组比较有显著差异(P<0.05),R3与P3组比较无显著差异(P>0.05)。SOD活性:R1与P1组比较有显著差异(P<0.05),R2与P2组比较有显著差异(P<0.05),R3与P3组比较无显著差异(P>0.05)。Johnsen's评分:R1与P1组比较有显著差异(P<0.05),R2与P2组比较无显著差异(P>0.05),R3与P3组比较无显著差异(P>0.05)。凋亡指数:R1与P1组比较有显著差异(P<0.05),R2与P2组比较无显著差异(P>0.05),R3与P3组比较无显著差异(P>0.05)。电镜:P1组超微结构损伤程度较R1组轻,R2与P2组超微结构无明显差异,R3与P3组超微结构无明显差异。结论:缺血后处理可以减轻睾丸缺血再灌注损伤,但是受到缺血程度的影响,并且在病理学和生化学上的表现不一致。     

缺血预处理对肾脏缺血再灌注损伤保护作用的研究进展

肾缺血再灌注损伤导致急性缺血性肾衰竭在临床上十分常见.研究显示缺血预处理对肾缺血再灌注损伤具有保护作用.近年来关于肾缺血预处理作用机制的报道较多,本文就缺血预处理对肾缺血再灌注损伤保护作用的研究现状作一综述.     

缺血预处理对肝脏缺血再灌注损伤保护作用的实验研究

在大鼠肝脏缺血再灌注模型基础上建立稳定的缺血预处理模型,观察其保护作用,结果发现预处理与缺血再灌注组相比比清肝酶（ＡＬＴ,ＡＳＴ）,透明质酸水平及肝组织局部ＭＤＡ含量均低,而组织ＡＴＰ含量及能荷值均高,形态学损伤改变轻;同时发现预处理组织腺苷含量明显高于缺血再灌注组。实验表明缺血预处理能有效减轻肝脏的缺血再灌注损伤,腺苷分子参与了这一保护机制。     

预缺血对肝脏缺血再灌注损伤的保护作用

已有较多的实验证明,预缺血处理对多种缺血再灌注器官有保护作用.本文综述了预缺血对缺血再灌注肝脏的保护作用及其机理.     

黄芪注射液对大鼠扭转复位后睾丸组织的保护作用

目的:探讨黄芪注射液对雄性Wistar大鼠扭转复位后睾丸的保护作用。方法:30只大鼠随机分为假手术组(A组)、睾丸扭转复位组(B组)、黄芪注射液治疗组(C组),每组10只,Turner法建立单侧睾丸扭转复位模型,原位缺口末端标记法检测各组睾丸组织中生殖细胞凋亡,化学比色法测定超氧化物歧化酶(SOD)和丙二醛(MDA)含量。结果:黄芪注射液治疗组与睾丸扭转复位组比较,SOD含量明显升高,MDA含量明显降低,生精细胞凋亡指数明显降低。睾丸扭转复位组、黄芪注射液治疗组与假手术对照组比较,SOD含量明显降低,MDA含量明显升高,生精细胞凋亡指数明显升高。结论:黄芪注射液可减少大鼠睾丸扭转复位后睾丸组织的双侧睾丸生殖细胞凋亡,对扭转复位后睾丸生殖细胞有保护作用。其机理可能与提高抗氧化酶活性及减少氧自由基的产生从而减轻大鼠睾丸扭转复位后的缺血再灌注损伤有关。     

Role of angiotensin and endothelin in testicular ischemia reperfusion injury

Objectives: To determine whether angiotensin and endothelin have any role in testicular ischemia reperfusion injury by investigating the effects of the angiotensin converting enzyme inhibitor enalapril, selective non‐peptide angiotensin‐II type I blocker losartan and dual endothelin receptor blocker bosentan. Methods: Rats were anesthetized with thiopental sodium (50 mg/kg i.p.) before the operation. The left testicular artery and vein of rats were occluded for 1 h; before the bilateral orchiectomy, the organ was allowed to reperfuse for 3 h or 24 h. Enalapril (20 mg/kg i.p.), losartan (30 mg/kg i.p.), bosentan (10 mg/kg i.p.) or vehicle (saline) were given 30 min before reperfusion. Malondialdehyde level was measured in testicular tissue after 3 h of reperfusion. Histological examination was carried out after 24 h of reperfusion. Results: Ischemia reperfusion caused a significant increase in malondialdehyde level of ipsilateral testis, and histopathological injury in both ipsilateral and contralateral testes. Enalapril, losartan and bosentan treatments prevented the ischemia reperfusion‐induced augmentation in malondialdehyde levels. Only bosentan treatment ameloriated ischemia reperfusion‐induced histopathological alterations. Conclusions: Endothelin might play a more important role in pathogenesis of testicular ischemia reperfusion injury when compared with angiotensin.     

红景天甙对大鼠肾脏缺血再灌注损伤的保护作用

目的探讨红景天甙对大鼠肾脏缺血再灌注损伤（IRI）的预防和保护作用。方法将32只健康成年SD大鼠随机分成正常对照组、假手术组、缺血再灌注组和红景天甙组4组，每组8只。缺血再灌注组和红景天甙组分别制作肾脏缺血再灌注模型，红景天甙组予以红景天甙预处理。检测血中尿素氮（BUN）和肌酐（Scr）及肾脏中超氧化物歧化酶（SOD）、丙二酰二醛（MDA）和钠钾ATP酶（Na^＋-K^＋ATPase）含量，并用光镜和电镜观察肾脏组织形态学变化。结果红景天甙组血清BUN和Scr水平、肾皮质MDA含量较缺血再灌注组显著降低（P〈0．01），而肾皮质中SOD和Na^＋-K^＋ATPase含量与缺血再灌注组相比显著升高（P〈0．01）；肾组织光镜和电镜观察均见缺血再灌注组肾小球和肾小管上皮细胞损伤明显，而红景天甙组肾小球及肾小管仅见轻微损伤。结论红景天甙能有效降低大鼠肾脏缺血再灌注损伤（IRI），对肾脏IRI有明显的预防和保护作用，为临床上肾脏IRI提供新的预防和治疗思路。     

Investigation of the protective effect of nesfatin-1 on testicular ischaemia-reperfusion damage: An experimental study

This study aimed to determine oxidative stress in the tissue after testicular torsion biochemically and histopathologically and to examine the effects of Nesfatin-1 treatment on this injury. Thirty-two rats were randomly divided into four groups: sham, torsion + detorsion (4 hr torsion followed by 1 hr detorsion), ischaemia/reperfusion + saline (I/R + S) and I/R + nesfatin-1. I/R + S group a single-dose saline treatment was administered intraperitoneally at the two-hundred-tenth minute of torsion (ischaemia; 10 cc/kg). Similarly, I/R + nesfatin-1 group a single dose of nesfatin-1 treatment was administered intraperitoneally at the two-hundred-tenth minute of ischaemia (10 µg/kg). Myeloperoxidase, total oxidant status and oxidative stress index values were significantly increased in the I/R and I/R + S group compared to the sham group. Superoxide dismutase was significantly decreased in the I/R + S group compared to the sham group. No significant difference was found between the I/R + nesfatin-1 group and the other I/R groups (I/R and I/R + S) in terms of biochemical parameters. The mean diameter of the seminiferous tubule decreased in the I/R groups. However, the mean diameter of the seminiferous tubules was not significantly different between the I/R + S group and the I/R + nesfatin-1 group. Thus, the administration of nesfatin-1 after ischaemia did not reduce testicular-oxidative stress.     

Beneficial effects of melatonin compared with allopurinol in experimental testicular torsion

Background/purpose

Several antioxidant agents such as allopurinol have been used to prevent ischemia-reperfusion (I/R) injury-induced tissue damage after experimental testicular torsion so far. The current study was designed to determine the effect of melatonin, which is a potent antioxidant agent, in preventing testicular damage following torsion.

Methods

Sixty prepubertal male Wistar-Albino rats were divided into 5 groups: control (C), torsion (T), torsion plus detorsion (TD), torsion plus allopurinol (200 mg/kg) plus detorsion (A), and torsion plus melatonin (50 mg/kg) plus detorsion (M). Left testes were rotated 720° for 6 hours. The torsed testes were detorsed. Detorsion time was 6 hours. In all groups, left orchiectomies were performed to determine the tissue levels of malondialdehyde (MDA) and histopathologic changes. Blood samples were taken to measure serum creatine phosphokinase (CPK) levels. The results were analyzed statistically.

Results

Serum CPK levels of groups A and M were found to be significantly lower than groups T and TD (P < .05). Tissue MDA levels in group M were statistically different from groups T and TD (P < .05). However, in groups A and T, MDA levels were similar (P > .05). The highest histologic grade was determined in group TD (3.8 ± 0.5). Histologic grade of group M was significantly lower than group TD (P < .001), but there was no histologic difference between testes of groups A and TD (P > .05).

Conclusions

These results have shown that melatonin treatment prevents I/R injury both biochemically and histopathologically, whereas allopurinol treatment prevents it only biochemically in experimental testicular torsion. Melatonin is a potent antioxidant agent more effective than allopurinol in preventing testicular I/R injury.     

L-精氨酸对大鼠胰腺移植缺血再灌注损伤的保护作用及其机制

目的探讨L-精氨酸（L-Arginine，L-Arg）对大鼠胰腺移植缺血再灌注（I／R）损伤的影响及其机制。方法SD大鼠作为供、受体行胰腺移植术，给予不同方式处理：假手术组（Sham）：只行开腹术；对照组（Control）：只行胰腺移植术，不行预处理；缺血预处理组（IPC）：在供胰切取前阻断血供10min，然后再灌注10min；L-精氨酸组（L-Arg）：行胰腺移植术，再灌注前先经下腔静脉注射L-Arg 10mg／kg体重；L-硝基精氨酸甲酯组（L-NAME）：供胰切取时阻断血供10min，再灌注10min；然后行移植术，在再灌注前，先经下腔静脉缓慢注射L-NAME 10mg／kg体重。各组手术完成后，于再灌注6h检测血清淀粉酶、肿瘤坏死因子-α（TNF-α）和一氧化氮（NO）水平，胰腺细胞凋亡指数、胰腺细胞bcl-2蛋白表达情况和胰腺组织病理改变。结果L-Arg和IPC都降低TNF-α水平（P〈0．01）和细胞凋亡水平（P〈0．01），NO水平升高（P〈0．01）。而L-NAME可阻断该保护效应。IPC和L-Arg均能激活bcl-2蛋白的表达。结论L-Arg可以模拟IPC对大鼠胰腺移植I／R损伤的保护作用，其机制与合成NO，激活bcl-2基因的表达有关。     

Quercetin has a protective role on histopathological findings on testicular ischaemia-reperfusion injury in rats

We investigated the effects of quercetin on pathological findings on testicular ischaemia-reperfusion (I/R) injury in rats. Twenty-four male Wistar albino rats were randomly assigned into four groups: Group 1, control (n = 5); Group 2, sham (n = 4); Group 3, I/R (n = 8); and Group 4, I/R + quercetin (n = 7). Bilateral testicular artery and vein were occluded for 1 h, followed by reperfusion in I/R and I/R + quercetin animals. Quercetin (20 mg kg(-1) per day) was administrated once daily by gavage to Group 1 and Group 4, respectively, after reperfusion. At the end of the study, bilateral orchiectomies were performed for histopathologic examination. The tissue damage was evaluated with light microscopy. Normal inter-stitium and seminiferous tubules were observed in control group. In the sham group, rats were seen minimal oedema around the seminiferous tubules and congested vascular structures. In Group 3, oedema, vascular congestion and haemorrhage between seminiferous tubules were observed. In Group 4, histopathologic features were markedly less than Group 3 (P = 0.03). Our study demonstrated that quercetin seems to have a protective effect on testis histopathology in rats with testicular I/R.     

不同意识状态下大白兔单侧睾丸急性缺血对健侧睾丸影响的实验研究

目的:比较麻醉态与清醒态兔单侧睾丸急性缺血对健侧睾丸血流动力学和病理的影响。方法:42只雄性健康大白兔,随机均分为麻醉组(A)和清醒组(B),各组内再设对照组5只(A0/B0)、不全缺血组8只(A1/B1)、完全缺血组8只(A2/B2)。超声监测下制成单侧睾丸急性缺血模型。缺血组于精索结扎前、后及松解前后相应时间行睾丸超声造影;对照组于相应时间行睾丸超声造影并监测心率、血压。分析两种意识状态下健侧睾丸造影及组织结构变化情况。结果:戊巴比妥钠麻醉后,A组兔心率、血压明显受抑制。单侧睾丸急性缺血后,A组健侧睾丸各造影参数无显著变化;B组健侧睾丸短时间内造影参数峰值基础强度差(PBD)减少,显影时间(AT)、峰值减半时间(HT)延长。精索松解后,A1组、B1组、B2组短时间内PBD增高、HT延长。缺血组健侧睾丸均存在局灶性病理损伤和超微结构变化,但Johnsen's评分各组无显著差异;A1组、B1组、B2组健侧睾丸凋亡细胞显著增多。结论:急性睾丸血运障碍可对健侧睾丸造成一定程度的损伤。清醒状态下一侧睾丸急性缺血可引起健侧睾丸血流动力学短期内的变化,神经血管反射可能是一重要原因。麻醉剂对兔神经及心血管的抑制作用可使健侧睾丸血流灌注变化不显著。     

Protective effects of Stevia rebaudiana aqueous extract on experimental unilateral testicular ischaemia/reperfusion injury in rats

This project aimed to examine Stevia rebaudiana aqueous extract protective effects on testicular ischaemia/reperfusion injury of rats. Forty rats were randomly divided into five groups: (1) sham group, (2) torsion/detorsion group, (3 and 4) low and high doses treatment groups received S. rebaudiana extract intraperitoneally 30 min before detorsion by 500 and 1,000 mg/kg respectively, and (5) healthy group received the extract by 1,000 mg/kg. In this study, left testes were rotated 2 hr, reperfusion period took long 5 hr, and then orchiectomy was performed. Histopathological and biochemical evaluations of testicular tissue samples were performed. Histopathologically, sham and healthy groups exhibited normal seminiferous tubules. Germinal cell necrosis, interstitial oedema, haemorrhage and congestion were seen in torsion/detorsion group. Testicular tissues of both treatment groups revealed lower histopathological alterations. Significant higher malondialdehyde level was observed in torsion/detorsion group than sham and healthy groups (p < .05). Compared with torsion/detorsion group, S. rebaudiana extract significantly reduced malondialdehyde level in treatment groups (p < .05). Torsion/detorsion group had significantly lower glutathione peroxidase and superoxide dismutase activities than sham and healthy groups, and these parameters showed significant increase in treatment groups compared with torsion/detorsion group (p < .05). The results revealed S. rebaudiana has this potential to protect the testes from ischaemia/reperfusion injury.     

The protective effect of darbepoetin alfa on experimental testicular torsion and detorsion injury

AIM: Testicular torsion is a serious urological emergency, usually involving newborns, children, and adolescents which can lead to subfertility and infertility. Prevention of testicular damage caused by torsion is still a clinical and experimental problem. So far many chemicals and drugs have been investigated for decreasing ischemia/reperfusion (I/R) injury in experimental animals. The possible protective effect of darbepoetin alfa, a novel erythropoietic protein, on testicular tissue after I/R injury was examined in this study. METHODS: Thirty rats were divided into three groups: sham operation, torsion/detorsion, and torsion/detorsion plus darbepoetin alfa groups. After torsion (2 hours) and detorsion (4 hours), bilateral orchiectomy was performed. Malondialdehyde, nitric oxide and glutathione levels were determined in testicular tissue. RESULTS: Administration of darbepoetin alfa caused a decrease of malondialdehyde and nitric oxide levels and an increase in glutathione levels compared with the torsion/detorsion group. In addition, histological injury scores were significantly decreased in the treatment group more than the torsion/detorsion group. CONCLUSION: The results suggest that darbepoetin alfa may be a potential protective agent for preventing testicular injury caused by testis torsion.     

纳洛酮对脑缺血/再灌注损伤保护机制的研究进展

纳洛酮是阿片受体的特异拮抗剂,近年来大量实验证实纳洛酮对脑缺血/再灌注损伤具有保护作用.其作用机制包括以下几条途径:纳洛酮能竞争性阻断内源性阿片肽对神经功能的损害作用,减少自由基的产生、减轻钙超载、逆转神经细胞内Mg2+的下降、逆转兴奋性神经毒性、抑制炎症介质的产生、改善神经元能量代谢、抑制神经元细胞凋亡.现就这一领域内的最新进展作一综述.