Torsion In Rats Research Articles

Glucocorticoid hormone can suppress apoptosis of rat testicular germ cells induced by testicular ischemia

Objective: To evaluate the effect of dexamethasone, a potent synthetic glucocorticoid hormone, on apoptosis of testicular germ cells and vascular neutrophil adhesion after repair of testicular torsion in rats. Design: Controlled laboratory study. Setting: Department of Urology, Yamagata University School of Medicine, Yamagata, Japan. Animal(s): Fifty-one male Sprague-Dawley rats. Intervention(s): Dexamethasone, 10 mg/kg of body weight. Main Outcome Measure(s): Testicular germ-cell apoptosis (percentages of apoptotic tubules and apoptotic cells) and vascular neutrophil adhesion were assessed by using DNA nick-end labeling and the endothelial-neutrophil adhesion score, respectively. Result(s): Intravenous administration of dexamethasone at repair of 90-minute testicular torsion significantly inhibited testicular germ-cell apoptosis and vascular neutrophil adhesion. This inhibition was suppressed by intravenous injection of mifepristone, a glucocorticoid-receptor antagonist. Conclusion(s): Glucocorticoids can be administered for torsion in addition to conventional torsion repair.

Fluctuations in rat testicular interstitial oxygen tensions are linked to testicular vasomotion: persistence after repair of torsion.

Testicular microvascular blood flow is known to exhibit vasomotion, which has been shown to be significantly altered in the short term following the repair of testicular torsion. This loss of vasomotion may ultimately be responsible for the loss of spermatogenesis observed after testicular torsion in rats. In the present study, testicular vasomotion and interstitial oxygen tensions were simultaneously measured prior to, during, and at various time points after repair of testicular torsion in the rat. Testicular torsion was induced by a 720 degrees rotation of the testis for 1 h. Laser-Doppler flowmetry and an oxygen electrode were used to simultaneously measure vasomotion and interstitial oxygen tensions (PO(2)), respectively. Pretorsion control testes had a mean blood flow of 16.3 +/- 1.3 perfusion units (PU) and displayed vasomotion with a cycle frequency of 12 +/- 0.2 cycles per minute and a mean amplitude of 4.2 +/- 0.3 PU. Mean testicular interstitial PO(2) was 12.5 +/- 2.6 mm Hg, which displayed a cyclical variation of 11.9 +/- 0.4 cycles per minute with a mean amplitude of 2.8 +/- 0.8 mm Hg. During the torsion period, both mean blood flow and interstitial PO(2) decreased to approximately zero. Upon detorsion, mean microvascular blood flow and mean interstitial PO(2) values returned to values that were not significantly different from pretorsion values within 30 min; however, vasomotion and PO(2) cycling did not return, even after 24 h. It was 7 days after the repair of torsion before a regular pattern of vasomotion and PO(2) cycling returned. These results demonstrate for the first time a correlation between testicular vasomotion and interstitial PO(2) cycling, and this correlation persists after the repair of testicular torsion.

Determination of testicular function after torsion by DNA flow cytometry of serial fine-needle aspirates.

To determine the efficacy of DNA flow cytometric analysis of testicular percutaneous fine-needle aspirates in the assessment and follow-up of testicular function after torsion, and to determine the relationship between the duration of torsion and testicular injury. Three groups of 15 adult rats underwent a 720 degrees torsion, with fixation of the mesorchial ligament, for 1, 3 or 5 h. Bilateral aspirations, performed 7, 21 and 35 days after torsion were examined by flow cytometry. Testes were harvested and evaluated histologically using Johnsen's scoring. Irreversible testicular injury occurred in all three groups of rats, with loss of function after 1 h and loss of viability after 3 and 5 h. The results from flow cytometry suggested significant contralateral testicular injury (P < 0.025) but this was not supported by the histological evaluation. There was a strong correlation between the testicular function assessed by flow cytometry and by Johnsen's scoring of histological specimens (r2 = 0.95). The assessment of testicular aspirates by flow cytometry allows testicular function to be followed after torsion in rats, and potentially in humans. Using DNA flow cytometry, the temporal course of the twisted testis in the adult rat was determined; contralateral testicular injury following the reversal of torsion could not be excluded.

The effect of vitamin E on ipsilateral and contralateral testis following unilateral testicular torsion in rats.

An experimental study was conducted to investigate the role of lipid peroxidation in ipsilateral and contralateral testicular reperfusion injury following unilateral testicular torsion (TT) and the effect of vitamin E in the management of this injury. Fifty adult male Sprague-Dawley rats were divided into five equal groups. Bilateral orchiectomy was performed immediately in group 1, and 3 h after unilateral TT in group 2. In group 3, both testes were harvested 3 h after a sham operation. In groups 4 and 5, unilateral TT, detorsion after 3 h and bilateral orchiectomy after 6 h were performed. Vitamin E was given before detorsion in group 4 and after detorsion in group 5. The levels of malondialdehyde (MDA) were measured as an index of lipid peroxidation in all testes. There were no significant differences between right and left testes within groups or between right or left testicular MDA values in different groups. The results suggest that lipid peroxidation does not play an important role in ipsilateral and contralateral testicular injury following unilateral TT and that vitamin E given before or after detorsion of testes is not useful in preventing testicular reperfusion injury.

The effect of vitamin E on ipsilateral and contralateral testis following unilateral testicular torsion in rats

The effect of vitamin E on ipsilateral and contralateral testis following unilateral testicular torsion in rats

Nonpulsatile arterial waveforms: Observations during graded testicular torsion in rats

We tested whether testicular torsion could completely damp distal arterial pulsatility, resulting in venous-appearing arterial waveforms. Progressively increasing testicular torsion was unilaterally produced in five rats. Doppler waveforms of the testicular artery distal to the torsion were obtained as soon as possible after each level of torsion until a complete absence of pulsatility was noted. One animal was not studied further after the first 180 degrees of torsion occluded flow. In three of the remaining four animals, the testicular artery resistive index (RI) at baseline (0.51, 0.58, 0.64) was within the range of the normal human intratesticular RI and decreased with increasing torsion, culminating in nonpulsatile, venous-appearing waveforms at high degrees of torsion. Testicular torsion can completely damp arterial pulsatility, resulting in nonpulsatile, venous-appearing arterial Doppler waveforms.

Is ipsilateral testis mandatory for contralateral testicular deterioration encountered following spermatic cord torsion?

Although deteriorating effects of unilateral spermatic cord torsion are generally accepted, the mechanism remains controversial. An experimental study was performed to evaluate the necessity of testicular and spermatogenetic material for contralateral testicular deterioration following unilateral spermatic cord torsion in rats. The animals were allocated to four groups: control, spermatic cord torsion, subepididymal orchiectomy, and spermatic cord torsion 14 days after subepididymal orchiectomy. The testes were removed on the 14th days and mean seminiferous tubular diameters and mean testicular biopsy scores were determined. Although contralateral testicular deterioration was more pronounced in the presence of testicular tissue, the absence of testicular tissue and/or spermatogenetic material did not prevent its occurrence. This is highly suggestive that autoimmune mechanism does not play a role in contralateral testicular damage following unilateral spermatic cord torsion.

The Alterations of Cellular Metabolism in the Contralateral Testis Following Spermatic Cord Torsion in Rats

Cellular metabolic study was performed on the contralateral testis after torsion to delineate early testicular changes. In 9-week-old Sprague-Dawley rats the left testicle was rotated and fixed to the scrotum for 3, 8 and 24 hours in 3 groups (I, II and III). Each group was divided into 3 subgroups (a, b and c) by the length of detorsion of 0, 4 hours and 14 days. We measured adenosine triphosphate, total adenosine nucleotides and adenylate energy charge of the contralateral testis by high performance liquid chromatography. Compared to controls, no subgroups showed differences in the histological parameters. Also in subgroups Ia, Ib, Ic and IIa none of the metabolic parameters were significantly altered. However, subgroups IIb and IIc, and group III and its subgroups showed significantly decreased levels of all metabolic parameters. Therefore, it appears that unilateral testicular torsion (greater than 8 hours) and detorsion affect the contralateral testicular metabolism without gross histological changes in rats, and these changes seem to be reversible in terms of cellular recoverability because the maximally decreased level of adenylate energy charge among all subgroups is only 13% compared to controls. These findings suggest that some systemic mechanisms rather than an immunological or local inflammatory process is involved in this early period after torsion.

1116 (accepted) - Immunologic and Morphological Effects of Spermatic Cord Torsion in Rats of Different Strains

No AccessJournal of Urology1 Jun 1987Immunologic and Morphological Effects of Spermatic Cord Torsion in Rats of Different Strains George F. Owens, Thomas Tarter, Jack Bruder, Anthony A. Fiore, and Stanley J. Kogan George F. OwensGeorge F. Owens More articles by this author , Thomas TarterThomas Tarter More articles by this author , Jack BruderJack Bruder More articles by this author , Anthony A. FioreAnthony A. Fiore More articles by this author , and Stanley J. KoganStanley J. Kogan More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(17)76264-7AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "Immunologic and Morphological Effects of Spermatic Cord Torsion in Rats of Different Strains." The Journal of Urology, 137(6), p. 382A © 1987 by The American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 137Issue 6June 1987Page: 382A Advertisement Copyright & Permissions© 1987 by The American Urological Association Education and Research, Inc.MetricsAuthor Information George F. Owens More articles by this author Thomas Tarter More articles by this author Jack Bruder More articles by this author Anthony A. Fiore More articles by this author Stanley J. Kogan More articles by this author Expand All Advertisement PDF downloadLoading ...

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.