The effects of vasodilatation and chemical sympathectomy on spermatogenesis after unilateral testicular torsion: a flow cytometric DNA analysis

Testicular Torsion and Spermatogenesis

Testicular torsion (TT) is a common urologic emergency that can occur at any age. It is most common in newborns and during puberty. Prompt evaluation and management is required to salvage the testis following an episode of torsion. TT brings about damage to testicular tissue and spermatogenesis through various hypothesized mechanisms; however there is a consensus that the effects of ischemia, ischemia-reperfusion injury, and oxidative stress account for the most destructive effects. Numerous studies have examined the effects of various agents and therapies in limiting the effects of TT on the testis.

Mechanisms of testicular torsion and potential protective agents

Testicular torsion is a urological emergency most commonly seen in adolescence, involving a decrease in blood flow in the testis resulting from torsion of the spermatic cord that can result in gonad injury or even loss if not treated in time. Testicular ischaemia-reperfusion injury represents the principle pathophysiology of testicular torsion, with ischaemia caused by twisting of the spermatic cord, and reperfusion on its subsequent release. Many cellular and molecular mechanisms are involved in ischaemia-reperfusion injury following testicular torsion. Studies have investigated the use of pharmacological agents as supportive therapy to surgical repair in order to prevent the adverse effects of testicular torsion. Numerous substances have been proposed as important in the prevention of post-ischaemia-reperfusion testicular injury. A range of chemicals and drugs has been successfully tested in animal models for the purpose of mitigating the dangerous effects of ischaemia-reperfusion in testis torsion.

Effects of chemical sympathectomy on contralateral testicular histology and fertility in unilateral vasectomy

Unilateral obstruction or injury to the vas deferens can result in significant injury to the contralateral testicle. Although various pathways have been proposed, the mechanism of contralateral testicular deterioration remains controversial. The present animal study was performed to evaluate the effects of unilateral vasectomy on ipsilateral and contralateral testicular histology and fertility in rats that were chemically sympathectomized neonatally. The study comprised 40 male albino rats: 20 received a placebo and the other 20 underwent chemical sympathectomy neonatally. When 60 days old, each group of 20 rats was divided into two groups that underwent either a sham operation or an operation to create unilateral left vasectomy. Eight weeks after surgery, each male rat was housed with two known fertile female rats for 25 days, and then their testes were harvested. Mean seminiferous tubular diameters (MSTD) and mean testicular biopsy scores (MTBS) were determined for each testis. Although MSTD and MTBS were not significantly different between groups, chemical sympathectomy prevented the decrease in total fertility rates of the rats with unilateral left vasectomy in our study. Prevention of this decrease by chemical sympathectomy suggests that the sympathetic nervous system may play a role in the testicular degeneration associated with vasectomy.

Long-term effect of pentoxifylline and NG-nitro-L-arginine methyl ester on testicular function in spermatic artery ligation

OBJECTIVE

To investigate long-term testicular function in pentoxifylline- and NG-nitro-L-arginine methyl ester (L-NAME)-treated rats prior to spermatic artery ligation by assessing serum inhibin B concentration, a reliable endocrine marker of spermatogenesis.

MATERIAL AND METHODS

Forty prepubertal rats were randomly divided into four equal groups. Right orchiectomy was performed in all rats. Intraperitoneal pentoxifylline and L-NAME were administered to Groups 1 and 2, respectively. Rats in Group 3 did not receive any medication. The spermatic arteries of the left testes were ligated in all groups with the exception of the sham controls (Group 4). One month postoperatively, a histopathologic evaluation was performed and serum inhibin B concentrations were assessed in all groups.

RESULTS

There were no statistically significant differences in testis size or serum inhibin B concentration between Groups 1, 2 and 3. However, the testes were significantly smaller (p(1)=0.01, p(2)=0.01, p(3)=0.01) and serum inhibin B levels were significantly decreased (p(1)=0.01, p(2)=0.01, p(3)=0.01) when Groups 1-3 were compared with Group 4. Histopathological evaluations revealed necrosis and calcification in all specimens with the exception of the sham-operated group.

CONCLUSIONS

The long-term outcomes of spermatic artery ligation were poor and testicular atrophy developed in rat testes in all study groups. Testicular atrophy could not be reversed by preoperative administration of pentoxifylline and L-NAME.

The effects of orchidopexy and orchidectomy on testes of rats subjected to ipsilateral abdominal testis with vas deferens obstruction

An experimental study was planned to evaluate and compare the effects of orchidopexy and orchidectomy on the testes of rats subjected to unilateral abdominal testis with vas deferens obstruction. Four groups were established. Rats in the control group underwent a sham procedure. While the testis was maintained in the abdomen with the vas deferens ligated for 8 weeks in group 2, rats in groups 3 and 4 underwent orchidopexy or orchidectomy after 4 weeks. Remaining testes were harvested at the end of the 8-week period. Testis and body weights were obtained during harvest. Samples were evaluated through DNA flow cytometry, and percentages of haploid cells were determined. Groups were compared through unpaired t-test, and p-values less than 0.05 were considered significant. All three treatments had decreased testis weight over body weight values of ipsilateral testes. Ipsilateral orchidectomy increased the value among contralateral testes. However, none of the groups had a contralateral testicular value less than the sham-operated group. All three treatments decreased the percentage of haploid cells among ipsilateral testes, but only an abdominal testis was associated with a decrease in the percentage of haploid cells among contralateral testes. Maintaining a testis with an obstructed vas deferens in the abdomen for 8 weeks damages both ipsilateral and contralateral testes. Orchidopexy, while showing amelioration of the ipsilateral testis, spares the contralateral testis as well as orchidectomy. Orchidopexy for an undescended testis with vas deferens obstruction is a rational approach.

Activation of endothelial nitric oxide synthase in contralateral testis during unilateral testicular torsion in rats

There are controversies about the injury of the contralateral testis during unilateral testicular torsion (UTT). An autonomic reflex arc between bilateral testes has been proposed. The authors focused on the involvement of nitric oxide (NO) in the contralateral testis during UTT. Eight-week-old male Wistar rats underwent unilateral torsion (1 h)-detorsion (up to 24 h). NO synthase (NOS) activity was detected as NADPH-diaphorase activity after fixation by paraformaldehyde. N-nitro-L-Arginine methyl ester (L-NAME, 20 mg/kg) was injected intravenously to the other group of rats. To evaluate the testicular injury, proteolysis of alpha-fodrin production was detected by Western blotting. Apoptosis of the germ cells was evaluated by TUNEL. Long-term effect on spermatogenesis was evaluated by flow cytometry at 60 days after UTT. Transient activation of NOS was detected following the proteolysis of alpha-fodrin in the contralateral testis. L-NAME inhibited these alterations. NADPH-diaphorase activity and eNOS immunoreactivity were co-localized in the endothelial cells. These reactions were not observed in other organs. There was neither enhanced apoptosis nor deteriorated spermatogenesis in the contralateral testis during and 60 days after UTT. In the contralateral testis, eNOS-derived NO regulates the vasomotor function against unilateral testicular torsion, whereas it acts slightly cytotoxic. These results suggest the possible involvement of a testis-specific neurovasomotor reflex between the bilateral testes.

The nontraumatic, acute scrotum

Regardless of age, any presentation of an acute scrotum requires prompt triage and immediate evaluation. The potential for significant reduction in morbidity and mortality exists if timely diagnosis and treatment are provided. Often overlooked, an early scrotal examination in the emergency department may produce the most accurate information into the underlying pathologic process, be it systemic or localized to the scrotum. Although the immediately lethal conditions presenting as acute scrotal pain should be considered, the combined incidence and morbidity associated with testicular torsion make its exclusion paramount in acute scrotal presentations. Similarly, a painless scrotal mass must be assumed to be a testicular neoplasm until proven otherwise, with appropriate work-up and rapid urologic follow-up assured.

Histopathological examination of both ipsilateral and contralateral testes with different obstructive models in prepubertal and adult rats

OBJECTIVE

To determine the histopathological changes in both the ipsilateral and contralateral testes of prepubertal and adult male rats 60 days after creating different obstructive models.

MATERIAL AND METHODS

Thirty-six prepubertal and 32 adult albino male rats were examined in three different obstructive models of the right testis. In group 1 the spermatic cord was ligated, in group 2 the ligation was between the caput epididymis and testis, and in group 3 the vas deferens was ligated. Sixty days after ligation both testes were removed and evaluated for testis diameter, mean seminiferous tubule diameter (MSTD), and degenerative, obstructive and inflammatory changes.

RESULTS

The diameter of the obstructed right testis and MSTD were significantly greater in prepubertal rats but there was no apparent difference in adult rats. For obstructive changes, sloughing of germ cells in the prepubertal rats and germ cell absence in adult rats were significantly more common in group 3. The contralateral testis diameter and MSTD of group 3 was significantly greater only in prepubertal rats. Statistically significant values of obstructive change, e.g. sloughing of germ cells and apical vacuolation in Sertoli cells, were apparent in prepubertal rats, but tubular ectasis was the only statistically significant criterion of obstruction in adult rats.

CONCLUSION

The testes are more susceptible to obstruction of the vas deferens in prepubertal than in adults rats, resulting in increased hydrostatic pressure and oedema of both the ipsilateral and contralateral testes, which might be caused by collateral circulation and rat testicular microcirculation, with a rhythmic pattern of arteriolar dilatation and constriction (vasomotion). Although the presence of oedema and high hydrostatic pressure was not prominent in adults, formation of spermatic granulomas and absence or sloughing of germ cells in the obstructed and contralateral testes reflect the early effects of vas ligation on spermatogenesis in adulthood.

Do experimentally induced ipsilateral testicular torsion, vas deferens obstruction, intra-abdominal testis or venous obstruction damage the contralateral testis through a common mechanism?

OBJECTIVE

To evaluate if various conditions affecting the ipsilateral testis which also damage the contralateral testis share a common pathway for their effects.

MATERIALS AND METHODS

The study comprised five groups of 10 adult rats which underwent surgery to produce (on their left sides); group 1, a sham operation (control); group 2, testicular torsion; group 3, vas deferens obstruction; group 4, an intra-abdominal testis; and group 5, venous obstruction. The ipsilateral and contralateral testes were harvested 4 weeks after surgery. The relative proportions of haploid cells, the mean seminiferous tubular diameter (MSTD), mean testicular biopsy scores (MTBS), and lactate and hypoxanthine levels were determined and compared.

RESULTS

The proportions of haploid cells in the ipsilateral and the contralateral testes of groups 2-5 were significantly lower than those of the corresponding testes of the control group. The MSTD and MTBS of the ipsilateral testes in groups 2-5 were also significantly lower than the ipsilateral testes of controls and the contralateral testes within the same groups. While the MSTD and MTBS of the contralateral testes of groups 1 and 5 were not significantly different, those of the contralateral testes of groups 2-4 were significantly less than that of group 1. The lactic acid and hypoxanthine levels of the ipsilateral and contralateral testes were significantly increased in groups 2 and 3. While only the hypoxanthine level of group 5 increased significantly, both variables were not significantly different between the ipsilateral testes of groups 1 and 4.

CONCLUSIONS

These four treatments damaged both the ipsilateral and contralateral testes. As the lactic acid and hypoxanthine levels within the contralateral testis were greater than in the controls, testicular torsion and vas deferens obstruction seem to share a common pathway (which may be a reflex decrease in contralateral testicular blood flow) for their effects on the contralateral testis.

The evaluation of sympathetic system-related contractile activity of the rat vas deferens after ligation and intra-abdominal placement of the testis

OBJECTIVE

To evaluate the contractile response of the vas deferens in a model of stress, to determine any changes in sympathetic activity as a result of stress in the ipsilateral testis, which decreases blood flow to the contralateral testis.

MATERIALS AND METHODS

The study comprised two groups of six rats each; group 1 underwent a sham operation, and in group 2 the right testis was placed into the abdominal cavity and the vas deferens ligated. After 30 days, the vasa deferentia were resected bilaterally and their isometric contractions recorded. Electrical-field stimulation (EFS) was applied through a pair of platinum electrodes and concentration-response curves constructed for noradrenaline at 37 degrees C and to a solution containing 80 mmol/L K+.

RESULTS

The vasa deferentia in both groups showed similar contractile responses to EFS, which were frequency-dependent and maximal at 80 Hz. Noradrenaline-induced contractile activity was lower in amplitude in the vasa deferentia of group 2 than in the contralateral and ipsilateral vasa deferentia of group 1, which were not significantly different from each other. All groups responded similarly to high K+.

CONCLUSION

Intra-abdominal placement of the testes with vas deferens ligation decreased the contractile response to noradrenaline in the ipsilateral vas deferens without altering the contractile response to EFS and high K+. This difference could be caused by a reduction in the number of postjunctional alpha-adrenergic receptors or decreased receptor sensitivity. Both possibilities suggest that the vas deferens may initiate sympathetic activity, which may be responsible for contralateral testicular deterioration.

Noradrenaline and nitrite-nitrate concentrations in the contralateral testes during ipsilateral spermatic cord torsion in the presence or absence of a testis and epididymis

OBJECTIVE

To determine the changes occurring during ipsilateral spermatic cord torsion either in the presence or absence of the ipsilateral testis and epididymis, by evaluating noradrenaline and nitrite-nitrate concentrations in the contralateral testes.

MATERIALS AND METHODS

Forty male albino rats were allocated randomly to one of four equal groups undergoing: group 1, a sham operation; group 2, ipsilateral spermatic cord torsion; group 3, epididymo-orchidectomy only; and group 4, spermatic cord torsion after epididymo-orchidectomy. The contralateral testes were harvested after 24 h and the noradrenaline and nitrite-nitrate contents determined. The levels in each group were compared using the Kruskal-Wallis and Mann-Whitney U-tests.

RESULTS

The noradrenaline content of testes from group 2 was significantly lower than in those of groups 1 and 3, but there were no significant differences in content between groups 1 and 3, 1 and 4, and 2 and 4. The content in group 4 was significantly less than that in group 3. There were no significant differences in nitrite-nitrate contents among any of the groups.

CONCLUSION

Spermatic cord torsion for 24 h, either in the presence or absence of a testis and epididymis, significantly decreased the noradrenaline content in the contralateral testis. This finding supports the suggestion that the sympathetic system is activated by exposure to noradrenaline in the contralateral testis during ipsilateral spermatic cord torsion, with no dependency on the presence of a testis and epididymis. As the nitrite-nitrate concentrations were unaffected, nitric oxide seems to have no role in contralateral testicular deterioration.