The effects of N-acetylcysteine on antioxidant enzyme activities in experimental testicular torsion

Testicular torsion is a serious problem in male children and, if not treated at the right time, can lead to subfertility and infertility. The main reason for testicular damage is ischemia-reperfusion injury. A number of chemical substances have been used to protect testes against ischemia-reperfusion injury in experimental animals. The possible protective effect of N-acetylcysteine on testicular tissue after testicular detorsion was examined in the current study. Twenty-four rats were divided into four groups: sham operation, torsion, detorsion, and NAC + detorsion groups (n = 6 for each group). Excluding sham operation group, the rats were subjected to unilateral torsion (720-degree rotation in clockwise direction). After torsion (5 h) and detorsion (2 h), unilateral orchidectomy was performed. Malondialdehyde levels and superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase activities were determined in testicular tissue. Administration of N-acetylcysteine caused a decrease in malondialdehyde levels and an increase in glutathione peroxidase levels compared to detorsion group. The results suggest that N-acetylcysteine may be a potential protective agent for preventing the negative biochemical changes related to oxidative stress in testicular injury caused by testis torsion.     

The effect of unilateral testicular torsion on the contralateral testicle in prepubertal Chinese hamsters

Recent studies of experimental testicular torsion in rats, rabbits, and guinea pigs have demonstrated conflicting evidence regarding contralateral testicular damage. Those studies in which cellular damage has been found are postulated to result from an immunological mechanism whereby the blood-testis barrier is disrupted with subsequent autoantibody formation. In this study, the histologic and immunologic effects of testicular torsion on the contralateral testicle were investigated in prepubertal Chinese hamsters. Four study groups were established; (1) Left orchiectomy only, (2) sham surgery (scrotal incision), (3) 720 degrees left testicular torsion with left orchiectomy 24 hours later, (4) 720 degrees torsion of left testicle with detorsion after 24 hours. The initial procedure was performed at 1 month of age with subsequent biopsies of the contralateral testicle at 1 week, 1 month, and 6 months after the initial procedure. Testicular tissue was examined for immunofluorescent activity using fluorescent labeled goat anti-hamster IgG. Positive controls were established by rabbit immunization (rabbit anti-hamster immunoglobulin) which was subsequently combined with fluorescent labeled goat antirabbit IgG. There was no appreciable difference in immunologic activity between control and experimental animals. Representative sections were examined histologically and no tubular damage was demonstrated and active spermatogenesis was noted at 6 months in all groups. We believe that our results support the premise that testicular torsion in the prepubertal period has no effect on the contralateral testicle.     

Unilateral testicular torsion: protective effect of verapamil on contralateral testicular histology.

In this experimental study, it was our aim to reduce the effects of ischemic insults to the contralateral testicle after unilateral testicular torsion. The protective effect of a calcium channel blocking agent (verapamil) on the histology and the tubular diameter of contralateral testicle was evaluated. Following a definite period of unilateral testicular torsion (i.e., 4 h), the protective effect of this specific medication was evaluated both after detorsion and orchiectomy procedures. The results of our study demonstrated the protective effect of verapamil on both parameters, especially in animals undergoing orchiectomy. The majority of the specimens demonstrated normal histologic findings together with preserved tubular structures after a 1-week period under verapamil medication.     

Protective role of natural antioxidant supplementation on testicular tissue after testicular torsion and detorsion

OBJECTIVES: To investigate the impact of garlic extract (GE), which is known for its antioxidant activity, on a testicular torsion/detorsion model in animals and to help understand how to prevent both ischemic and reperfusion injuries after testicular torsion and detorsion. MATERIAL AND METHODS: Six groups of rats (n=7 in each group) were used. The animals in the control group (Group I) did not receive any treatment. The animals in the sham group (Group II) underwent scrotal incision and testicular fixation only. The animals in Groups III-VI underwent 720 degrees of left testicular torsion for 2 h; subsequent detorsion was performed for 2h in Groups IV and VI only. Animals in Groups V and VI were treated exactly the same as those in Groups III and IV, respectively except that they were pretreated with oral GE for 5 days at a dosage of 5 ml/kg. Both testicles in all rats were removed and tissue malondialdehyde (MDA) levels and enzymatic activities of xanthine oxidase (XO) were studied, in addition to a histological evaluation after hematoxylin-eosin staining. RESULTS: Testicular MDA levels and XO activities were higher in Group III compared to Group II (p<0.05). Pretreatment with GE prevented these increases. Detorsion caused more damage and resulted in a further increase in MDA levels but MDA levels were not increased in animals pretreated with GE. Histologically, torsion caused some separation between germinative cells in the seminiferous tubules, which became much more prominent in Group IV and was attenuated by GE pretreatment. There were no significant changes in any of the above-mentioned enzymatic activities or histopathologic changes in the contralateral testicle in any of the groups. CONCLUSIONS: We believe that both testicular torsion and detorsion result in testicular tissue damage by means of lipid peroxidation, which is evident by an increase in the tissue levels of MDA. Dietary supplementation with GE seems to attenuate the generation of toxic free radicals, as evidenced indirectly by low tissue MDA levels.     

Pentoxifylline attenuates reperfusion injury in testicular torsion

OBJECTIVES: An experimental study was designed to evaluate the effects of pentoxifylline (Ptx) on lipid peroxidation, and histopathology in both testes after unilateral testicular torsion and detorsion. MATERIALS AND METHODS: Forty adult male albino Wistar rats were randomly divided into 4 groups of sham operation, sham operation with Ptx, torsion and detorsion, torsion and detorsion with Ptx. After intraperitoneal administration of Ptx at a dose of 50 mg/kg 15 min before torsion; right testes of the rats underwent 30 min of torsion and 30 min of detorsion. Malondialdehyde (MDA) levels were assayed and histopathological changes were evaluated in both testes of all groups. RESULTS: Unilateral testicular torsion and detorsion caused an increase in the MDA levels of both testes. Histopathological evaluation showed interstitial hemorrhage on the ipsilateral side. Pentoxifylline decreased MDA levels on both side, and attenuated interstitial injury on the ipsilateral side. CONCLUSIONS: The results of this study suggest that pentoxifylline treatment attenuates reperfusion damage on both side, possibly with its effects on blood flow and neutrophils. However, further studies are necessary to evaluate the effects of pentoxifylline on testicular torsion.     

Testicular oximetry: a new method for the assessment of tissue perfusion and viability following torsion and detorsion

This study evaluated the use of a polarographic surface PO2 electrode to assess testicular perfusion and viability following torsion and detorsion. Adult male Sprague-Dawley rats were divided into groups and subjected to unilateral testicular torsion and detorsion of varying degrees and durations. Rats subjected to sham torsion or 720 degrees torsion did not show significant decreases in testicular PO2 after 15 minutes, whereas those subjected to 1,080 degrees torsion or spermatic cord ligation uniformly decreased their testicular PO2 to 0 mm Hg within 10 minutes. Testicular PO2 values were similar in rats subjected to 60 minutes of 720 degrees torsion followed by detorsion and those undergoing 15 minutes of 1,080 degrees torsion and detorsion. Rats subjected to breathing 100% oxygen uniformly increased their testicular PO2 to an average of more than twice room-air values. However, rats subjected to 1,080 degrees torsion for 6 hours followed by detorsion did not increase their testicular PO2 when subjected to breathing 100% oxygen, whereas those subjected to 720 degrees torsion for 6 hours followed by detorsion did increase their testicular PO2 when subjected to breathing 100% oxygen. The latter rats did not show microscopic changes associated with acute testicular infarction, whereas the former did.(ABSTRACT TRUNCATED AT 250 WORDS)     

己酮可可碱对大鼠睾丸扭转复位后生精功能的保护

目的:探讨己酮可可碱(PTX)对大鼠睾丸扭转复位后生精功能的保护作用。方法:雄性SD大鼠24只,随机分成3组,每组8只,建立睾丸扭转动物模型。第Ⅰ组为假手术组(扭转720°后立即复位),第Ⅱ、Ⅲ组扭转720°2 h,于复位前15 m in分别静脉注射生理盐水和PTX,术后24 h留取手术侧睾丸。应用流式细胞术(FCM)检测各组生精细胞凋亡和各级生精细胞计数,采用硫代巴比妥酸法测定丙二醛(MDA)含量,化学比色法测定组织内总抗氧化能力(T-AOC)。结果:第Ⅲ组应用PTX后与第Ⅱ组相比,生精细胞凋亡明显减少(399.50±33.31vs1221.75±132.48,P<0.01),单倍体和四倍体细胞群计数显著增多(5554.13±441.28vs4102.35±206.98;1906.00±200.72vs1711.63±144.55,P均<0.01;),T-AOC明显回升(32.52±2.86vs22.76±3.73,P<0.01),MDA含量下降(1.78±0.20vs3.98±0.36,P<0.01),其差异均有显著性(P<0.01)。结论:己酮可可碱对睾丸扭转复位后的生精功能具有明显的保护作用。     

New animal model to evaluate testicular blood flow during testicular torsion.

BACKGROUND/PURPOSE: Unilateral testicular torsion is known to cause infertility because of damage to the contralateral testis. Testicular damage has been attributed to many different mechanisms, one of which is altered contralateral blood flow. In our experiment, in an effort to identify the reason for contralateral testicular injury, the authors developed an accurate method of measuring blood flow in both testes before, during, and after unilateral torsion. METHODS: Four- to 6-week-old piglets weighing 4 to 6 kg were studied. The animals were anesthetized, intubated, ventilated, and catheterized for vascular access. Piglets were assigned randomly to a sham group or a group undergoing 360 degrees or 720 degrees torsion of the left testis (n = 5 per group) for 8 hours, after which it was untwisted. Data were collected at baseline (T = 0), 8 hours of torsion (T = 8), and 1 hour after detorsion (T = 9). Mean arterial blood pressure and heart rate were monitored continuously. Testicular blood flow was determined using radiolabeled microspheres. Blood flow data were evaluated by analysis of variance. RESULTS: In the 360 degrees torsion group, blood flow changes were insignificant during torsion and after detorsion. In the 720 degrees torsion group, blood flow to the twisted testis was reduced significantly, whereas the contralateral testis was unaffected. One hour after detorsion, blood flow to both testes was increased significantly. CONCLUSIONS: The authors describe a new animal model to evaluate testicular blood flow during and after testicular torsion. Increased blood flow after detorsion may be the cause of testicular damage in patients with unilateral testicular torsion.     

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.     

The preventive effects of thiopental and propofol on testicular ischemia-reperfusion injury

BACKGROUND: Testicular torsion is a urological emergency that requires immediate surgical intervention to prevent testicular damage. The aim of the study was to investigate the preventive effects of thiopental and propofol as anesthetics on testicular ischemia-reperfusion injury. METHODS: Forty male Wistar Albino rats were randomly assigned to four groups of 10 rats each. During 5 h, anesthesia was induced and maintained with thiopental in groups 1 and 2 and with propofol in groups 3 and 4. Groups 2 and 4 received left testicular ischemia (torsion) during 1 h and reperfusion (detorsion) during 4 h. Groups 1 and 3 (control groups) had no testicular torsion and detorsion. At the end of 5 h, animals were killed and both ipsilateral and contralateral testes were removed for histopathologic examination and measurement of tissue MDA (malondialdehyde) and NO (nitric oxide) levels. RESULTS: In the contralateral testes of all the groups, MDA and NO measurements were not different from ipsilateral testes of the control groups. Between the groups 1 and 3, there were no differences in MDA and NO levels. Although torsion/detorsion of testes in group 4 caused significantly increased levels of tissue MDA and NO values compared with group 3, ischemia-reperfusion in group 2 caused a further increase in these levels compared with group 4. The ipsilateral testes in the control groups did not show any morphological changes. Testicular torsion/detorsion in rats with thiopental anesthesia (group 2) caused significantly greater histopathologic injury levels than rats with propofol anesthesia (group 4). CONCLUSION: Our results suggest that propofol as an anesthetic agent may prevent testicular damage by scavenging reactive oxygen and nitrogen species and inhibiting lipid peroxidation in an animal model of testicular torsion and detorsion.     

低温对大鼠睾丸扭转后睾丸抗氧化能力影响的研究

目的:探讨低温对睾丸扭转后其抗氧化能力的影响。方法:24只健康青春期SD雄性大鼠随机分为3组:A组为睾丸扭转组,B组为睾丸扭转加低温组,C组为对照组,每组8只。建立单侧睾丸扭转模型。术后第14d采集睾丸。化学比色法测定其总抗氧化能力(T-AOC)和丙二醛(MDA)的含量。光镜观察睾丸组织学变化。结果:B组T-AOC明显高于A组(P<0.01),而低于C组(P<0.01);B组MDA含量低于A组(P<0.01),而高于C组(P<0.05)。结论:低温可抑制睾丸扭转复位后氧自由基的产生及其引发的脂质过氧化反应,提高扭转睾丸的生存力。     

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。     

Effect of testicular torsion on the contralateral testis and prevention of this effect by prednisolone

This study was instituted to evaluate the effect of unilateral testicular torsion on contralateral testicular histology and the prevention of this effect by prednisolone. Fifty Swiss albino rats were equally divided into 5 groups. In group 1, it was observed that, due to torsion, the mean seminiferous tubular diameter and percentage of spermatogenetic activity of the contralateral testes were reduced and an inflammatory reaction was also noted. In group 2, detorsion increased the above-mentioned damage, and in group 3, orchiectomy failed to prevent it. In group 4, it was seen that prednisolone slightly increased the mean percentage of spermatogenetic activity and produced proliferation of the Leydig cells in the intact testicle. In group 5, when prednisolone was injected just after torsion, no damage to the contralateral testes appeared. It has been thought that damage to the contralateral testes may arise from an autoimmune mechanism and prednisolone appeared to be very helpful in preventing damage by immunologic suppression.     

Testicular fixation following torsion of the spermatic cord--does it guarantee prevention of recurrent torsion events?

PURPOSE: Patients with history of testicular torsion who have undergone orchiopexy may rarely present with acute scrotum due to recurrent episodes of torsion. Most of the reports in the literature regarding this scenario refer to the era when absorbable sutures were used for testicular fixation. Herein, we review our experience in recent years, focusing upon the surgical technique and sutures' material. MATERIALS AND METHODS: Between 1991 and 2003, 179 patients were operated on at our institute with the clinical diagnosis of unilateral testicular torsion. They ranged in age between neonates to 45 years old (average age 18). In a comprehensive retrospective study we managed to locate 8 patients who experienced recurrent intravaginal testicular torsion following previous fixation performed in our institute. RESULTS: The patients who experienced repeat torsion have initially presented at the mean age of 18.5 years old (range 12 to 30) with unilateral twisted testicle (left 3, right 5). Urgent explorations were generally performed, apart from in 2 cases that underwent spontaneous detorsion which was followed by an elective surgery. Testicular fixation was conducted by suturing of the tunica albuginea to the dartos layer by 2 sutures at each side, using chromic 3-zero in the 3 more early cases, followed by the usage of polyglactin 3-zero stitches in 4 subsequent cases and 3 sutures of polypropylene 4-zero for each testicle, thereafter, in the most recent case. The patients presented with repeat torsion, 0.5 to 23 years subsequently (average 7 years), involving either the ipsilateral testicle in 4 cases or the contralateral gonad in 4. CONCLUSIONS: Recurrent torsion following previous testicular fixation may appear many years following the primary procedure, even in cases in which either polyglactin or, notwithstanding, polypropylene sutures have been applied, in accordance with the common practice used in the last 2 decades. Increased awareness regarding this possibility is imperative for early diagnosis and prevention of testicular loss.     

Experimental testicular torsion and its effects on the contralateral testicle

Objective Following experimental unilateral torsion of the testis the histologic effects of unilateral testicular torsion on the contralateral testis were investigated. Materials and methods Utilizing detorsion or orchiectomy at 4 hours and 8 hours after torsion, the effects of early and late treatment modalities on the contralateral testicle were observed. Results Morphometry of the contralateral testis revealed some alterations including focal sclerosis, decrease in mean seminiferous tubular diameter and a marked increase of the Leydig cells in some subgroups. Conclusion In spite of some changes, definite evidence for contralateral damage due to ipsilateral torsion contributing to male infertility was hardly observed.     

生脉注射液对不同周龄大鼠睾丸扭转复位后睾丸损伤影响的研究

目的:探讨生脉注射液对不同周龄大鼠睾丸扭转复位后睾丸损伤影响的差异。方法:3、6、12周龄健康雄性SD大鼠各16只,随机分成睾丸扭转复位+注射生脉注射液组(实验组)和睾丸扭转复位+注射生理盐水组(对照组),每组8只,建立睾丸扭转动物模型(左侧阴囊切开,绕精索顺时针扭转睾丸720°2h),并于手术后24h处死,测定各组大鼠睾丸组织内总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)活性与丙二醛(MDA)含量。结果:与各自对照组比较,3、6周实验组大鼠左侧睾丸组织中T-AOC、SOD活性和MDA含量均无显著性改变(P>0.05);12周实验组大鼠左侧睾丸组织中SOD、T-AOC明显升高,而MDA含量显著降低,差异均具有显著性(P<0.05)。结论:生脉注射液对睾丸扭转复位后的缺血再灌注急性损伤有保护作用,但对不同周龄大鼠的再灌注损伤保护作用不同,存在年龄相关性差异,对较大周龄大鼠的急性保护作用较为明显。     

Torsion and the contralateral testicle

The histologic effect of unilateral torsion on the contralateral testicle in adult Noble rats was examined. Utilizing detorsion or orchiectomy at 3 hours and 24 hours after torsion, the effect of early and late treatment of these changes was reviewed. The histologic changes consisted of loss of tubular spermatozoa, clumping of chromatin within the spermatocytes, the presence of Sertoli-only cells, evacuolization of Sertoli cytoplasm and germinal epithelial sloughing. Depression of spermatogenesis and decrease in the mean seminiferous tubular size was seen in the "normal" testicle after unilateral torsion. This effect was negated by early treatment with either orchiectomy or detorsion. Late detorsion does not negate these effects and late orchiectomy only partially negates them. Despite the depressed tubular function, the presence of early spermatogenic elements seen in the majority of the tubules in the "normal" testicle implies the possible reversibility of these changes.     

Reperfusion injury after detorsion of unilateral testicular torsion

Summary Reperfusion injury has been well documented in organs other than testis. An experimental study was conducted to investigate reperfusion injury in testes via the biochemical changes after unilateral testicular torsion and detorsion. As unilateral testicular torsion and varicocele have been shown to affect contralateral testicular blood flow, reperfusion injury was studied in both testes. Given that testicular blood flow does not return after 720° testicular torsion lasting more than 3 h, the present study was conducted after 1 and 2 h of 720° torsion. Adult male albino rats were divided into seven groups each containing ten rats. One group served to determine the basal values of biochemical parameters, two groups were subjected to 1 and 2 h of unilateral testicular torsion respectively, two groups were subjected to detorsion following 1 and 2 h of torison respectively, and two groups underwent sham operations as a control. Levels of lactic acid, hypoxanthine and lipid peroxidation products were determined in testicular tissues. Values of these three parameters obtained from the sham operation control groups did not differ significantly from basal values (P>0.05). All three parameters were increased significantly in both ipsilateral and contralateral testes after unilateral testicular torsion when compared with basal values (P<0.01 and P<0.05, respectively). Detorsion caused significant changes in lipid peroxidation products levels in ipsilateral but not in contralateral testes when compared with values obtained after torsion (P<0.01 and P>0.05, respectively). It is concluded that ipsilateral testicular torsion causes a decrease in perfusion not only in the ipsilateral but also in the contralateral testis. Additionally, detorsion following up to 2 h of 720° torsion causes reperfusion injury in ipsilateral but not in contralateral testis.     

Effect of external scrotal cooling on the viability of the testis with torsion in rats

BACKGROUND AND AIM: Testicular damage due to ischemia during torsion is aggravated after reduction and reperfusion. The severity of the damage depends on the degree and duration of the torsion. Hypothermia has been successfully used in preserving the viability of ischemic organs for a prolonged period. Our aim is to evaluate the effect of external scrotal cooling in preserving testicular viability after spermatic cord torsion in rats. METHODS: 100 adult male Sprague-Dawley rats were equally divided into ten groups. Exposure of the right testicle for either 4 or 8 h in groups 1 and 2 were the control groups. The rats in eight groups (3-10) underwent clockwise torsion of 1,080 degrees of the right testis around its longitudinal axis, for either 4 or 8 h. External scrotal cooling was applied during the torsion period in four groups. Half of the rats were sacrificed at the end of the torsion period, while the other rats underwent detorsion and were sacrificed 2 weeks later. All testicles were excised for histology. RESULTS: The histological results showed that external scrotal cooling decreased both immediate and late damage to the testis, caused by torsion. A moderate degree of injury was found in the contralateral testicle in rats after torsion of the right testicle for 8 h with application of external cooling and detorsion. CONCLUSION: External scrotal cooling is effective in preserving the viability of the torsed testis in rats. The injury of ischemia-reperfusion, although reduced by external cooling, may endanger the contralateral testis as well, if the duration of torsion is longer than 4 h. With increased duration of torsion, orchiectomy should be considered. Application of this treatment may reduce the injury in humans awaiting surgery.     

Propofol attenuates reperfusion injury after testicular torsion and detorsion

Propofol, which is widely used as an intravenous anesthetic, has been shown to have an antioxidant activity on several tissues. This study was designed to investigate the prevention of reperfusion injury with propofol after testicular torsion. Five groups of rats (seven in each group) were used. Animals in the control group (group I) did not received any treatment, while animals in the sham group (group II) underwent scrotal incision and testicular fixation only. After 2 h of 720° left testicular torsion in groups III, IV and V, subsequent detorsion was done for 2 h in groups IV and V. Propofol (50 mg/kg) was injected transperitoneally 30 min prior to detorsion in group V. Both testicles in all rats were retrieved and tissue malondialdeyhde (MDA) level, which is a measure of the amount of free oxygen radicals, and enzymatic activity of xanthine oxidase (XO), which converts hypoxanthine to xanthine and uric acid were studied. In addition, tissue catalase (CAT) and glutathione peroxidase (GSH-Px) activities, which are endogenous scavenger enzymes, protecting tissues against free radicals, were studied. Additionally, histological evaluations were performed after hematoxylin and eosin staining. Testicular MDA levels, and XO and CAT activities were higher in the torsion group compared to sham control group (P<0.05). Detorsion caused a further increase in MDA levels, contrasting with a decrease in the levels of XO activity, while CAT activity was not changed. Pretreatment with propofol prevented a further increase in MDA levels and significantly decreased CAT activity following detorsion. GSH-Px activities were not effected either by torsion/detorsion or propofol pretreatment. Histologically, torsion caused some separation between germinal cells in the seminiferous tubules, which became much more prominent in the detorsion group and attenuated with propofol pretreatment. There was no significant change in any of the abovementioned enzymatic activities nor were there histopathological changes in the contralateral testicle in any groups. It is concluded that biochemically and histologically reperfusion injury occurs in the ipsilateral testis following detorsion up to 2 h. Preference of propofol for anaesthesia during the detorsion procedure may attenuate such reperfusion injury.