Structural study of gubernaculum testis in fetuses with prune belly syndrome.

PURPOSE: We compared and contrasted the structure of the gubernaculum testis in fetuses with prune belly syndrome and normal controls. MATERIALS AND METHODS: We studied a total of 6 gubernacula from 3 male fetuses with prune belly syndrome and a total of 14 from 7 male fetuses without an anomaly. Gubernacular specimens were cut into 5 µm sections and stained with Masson trichrome to quantify connective tissue and smooth muscle cells, with Weigert stain to observe elastic fibers and with picrosirius red with polarization to observe collagen. Immunohistochemical analysis was done with tubulin to observe the nerves. Images were captured with a BX51 microscope and DP70 camera (Olympus®). Stereological analysis was done with Image-Pro and ImageJ (MediaCybernetics®) using a grid to determine volumetric density. Means were statistically compared with the Mann-Whitney test. All tests were 2-sided with p <0.05 considered statistically significant. RESULTS: Prune belly syndrome fetuses were at 17 to 31 weeks of gestation and control fetuses were at 12 to 35 weeks of gestation. Quantitative analysis showed no difference in the volumetric density of smooth muscle cells in prune belly syndrome vs control gubernacula (mean 15.70% vs 19%, p = 0.2321). Collagen fiber analysis revealed a predominance of green areas in prune belly syndrome gubernacula, suggesting collagen type III, and a predominance of red areas in control gubernacula, suggesting collagen type I. Elastic fibers were significantly smaller in prune belly syndrome gubernacula than in control gubernacula (mean 14.06% vs 24.6%, p = 0.0190). Quantitative analysis demonstrated no difference in the volumetric density of nerves in prune belly syndrome or control gubernacula (mean 5.200% vs 3.158%, p = 0.2302). CONCLUSIONS: The gubernaculum in fetuses with prune belly syndrome had altered concentrations of collagen and elastic fibers. These structural alterations could be one of the factors involved in cryptorchidism in prune belly syndrome.

The importance of the gubernaculum in testicular migration during the human fetal period

Objectives The objective of this review is to study the role of the gubernaculum in the testicular migration process during the human fetal period. Materials and Methods We performed a descriptive review of the literature about the role of the gubernaculum in testicular migration during the human fetal period. Results In the first phase of testicular migration, the gubernaculum enlarges to hold the testis near the groin and in the second phase the gubernaculum migrates across the pubic region to reach the scrotum. The proximal portion of the gubernaculum is attached to the testis and epididymis and the presence of multiple insertions in the distal gubernaculum is extremely rare. The presence of muscle and nerves in the human gubernaculum is very poor. The gubernaculum of patients with cryptorchidism has more fibrous tissue and less collagen and when the patients are submitted to hormonal treatment, the gubernaculum components alter significantly. Conclusions The gubernaculum presents significant structural modifications during testicular migration in human fetuses. .

Testicular migration chronology: do the right and the left testes migrate at the same time? Analysis of 164 human fetuses.

OBJECTIVE: To determine if the right and the left testes migrate at the same time during the human fetal period. SUBJECTS AND METHODS: We studied 164 human fetuses (328 testes) ranging in age from 12 to 35 weeks post-conception. The fetuses were carefully dissected with the aid of a stereoscopic lens at ×16/25. The abdomen and pelvis were opened to identify and expose the urogenital organs. Testicular position was classified as: (a) Abdominal, when the testis was proximal to the internal ring; (b) Inguinal, when it was found between the internal and external inguinal rings); and (c) Scrotal, when it was inside the scrotum. RESULTS: The testes were abdominal in 71% of the cases, inguinal in 9.41%, and scrotal in 19.81%. There was asymmetry in testicular migration in nine cases (5.5%). In three of these nine cases, one testis was situated in the abdomen and the other in the inguinal canal; in another three one testis was situated in the abdomen and the other in the scrotum, and in the remaining three, one testis was in the inguinal canal and the other in the scrotum. In five of the nine cases of asymmetry, the right testis completed the migration first, but this was not statistically significant. CONCLUSION: Asymmetry in testicular migration is a rare event, accounting for <6% of the cases. The right testis seems to complete migration first.

The importance of the gubernaculum in testicular migration during the human fetal period.

OBJECTIVES: The objective of this review is to study the role of the gubernaculum in the testicular migration process during the human fetal period. MATERIALS AND METHODS: We performed a descriptive review of the literature about the role of the gubernaculum in testicular migration during the human fetal period. RESULTS: In the first phase of testicular migration, the gubernaculum enlarges to hold the testis near the groin and in the second phase the gubernaculum migrates across the pubic region to reach the scrotum. The proximal portion of the gubernaculum is attached to the testis and epididymis and the presence of multiple insertions in the distal gubernaculum is extremely rare. The presence of muscle and nerves in the human gubernaculum is very poor. The gubernaculum of patients with cryptorchidism has more fibrous tissue and less collagen and when the patients are submitted to hormonal treatment, the gubernaculum components alter significantly. CONCLUSIONS: The gubernaculum presents significant structural modifications during testicular migration in human fetuses.

The role of androgens in development of the scrotum of the grey short-tailed Brazilian opossum ( Monodelphis domestica).

In eutherian mammals, sex differentiation is initiated by expression of the testis-determining gene on the Y chromosome. Subsequent phenotypic development of the reproductive tract and genitalia depends on the production of hormones by the differentiated testis. In marsupials the mechanisms of phenotypic development may vary from this pattern, as differentiation of the scrotal primordia has been shown to occur before that of the gonad. Thus, the development of the scrotum in the marsupial has been regarded as an androgen-independent process. We have sought to clarify the ontogeny of scrotal development and the appearance of androgen receptor immunoreactivity by examining Monodelphis domesticaembryos/pups from 1 day prior to birth until 2 days after birth. We have also used immunocytochemistry to determine the expression of the key steroidogenic enzyme 3beta-hydroxysteroid dehydrogenase as an indicator of when the developing gonad may be capable of synthesizing androgens. Expression of this enzyme was first detected in the gonads and adrenals of both sexes 1 day prior to birth and before the appearance of scrotal bulges. Androgen receptor immunoreactivity was detected in the scrotal anlagen of male opossum pups as early as 1 day following birth. This finding is significantly earlier than previous reports and coincides with the appearance 1 day after birth of distinct scrotal bulges. Androgen receptor immunoreactivity was also observed in the genital tubercles of male pups, but not female pups, 2 days after birth. These results suggest that androgens may play an important role in the development of the male genitalia at a much earlier stage than that indicated by previously published work and that scrotal development in this species may not be androgen-independent.

Testicular migration: remodeling of connective tissue and muscle cells in human gubernaculum testis.

PURPOSE: We present the main morphological modifications in the human gubernaculum during testicular migration in humans. MATERIALS AND METHODS: We obtained 12 gubernacula from fresh, macroscopically normal human fetuses at 15 to 29 weeks of gestation. Collagen was evidenced using trichrome and Sirius red staining procedures, while Weigert's resorcinol-fuchsin and anti-human elastin antibody were used to reveal elastic system fibers. Smooth muscle cells were detected by anti-human smooth muscle alpha-actin antibody. RESULTS: When the testes were still located in the abdomen at 15 to 16 weeks of gestation, collagen fibers were sparse and embedded in a loose extracellular matrix. The amount of fibers then gradually increased with age and at 28 weeks of gestation the gubernaculum was mostly collagenous in composition. Elastic fibers had a similar growth pattern, although they were located mainly at the distal end of the gubernaculum. Fibroblasts largely predominated over other cell types and decreased in number with gestational age, whereas smooth muscle cells were restricted to the walls of blood vessels. Striated muscle cells were detected at the scrotal end of the gubernaculum, where they were disposed as isolated and scattered bundles running in various directions. Like fibroblasts, their number also decreased with age. CONCLUSIONS: During testicular migration gubernacular connective tissue undergoes extensive remodeling and ultimately becomes an essentially fibrous structure rich in collagen and elastic fibers. Such changes should decrease the size of the gubernaculum and, thus, contribute to other forces that cause the testes to move toward the scrotum. In fact, because of the lack of smooth muscle cells, and the amount and organization of striated muscle cells, active contraction of the gubernaculum is less likely to be an important factor in testicular descent.

Proximal insertion of gubernaculum testis in normal human fetuses and in boys with cryptorchidism.

PURPOSE: We determine how the proximal gubernaculum testis is attached to the testis and epididymis in human fetuses, and compare these data with findings in boys who had undergone surgery for cryptorchidism. MATERIALS AND METHODS: We analyzed 280 testes and epididymides with the gubernacula of 140 well preserved, fresh human fetuses ranging from 10 to 35 weeks after conception with no detectable congenital malformations and 36 undescended testes of 28 boys 2 to 15 years old (mean age 6.8) who had undergone surgery for cryptorchidism. In both groups the different conformations of the relationship among the proximal gubernaculum, testis and epididymis were classified according to a system used for patients with cryptorchidism. In group A the gubernaculum is attached to the testis and epididymis, in group B the gubernaculum is attached only to the testis with a tail disjunction epididymal anomaly, in group C the gubernaculum is attached only to the testis with total disjunction of the epididymis, in group D the gubernaculum is attached only to the epididymal tail and in group E there are no attachments among gubernaculum, testis and epididymis. RESULTS: Of the 280 fetal testes studied 194 (69.2%) were in the abdomen, 38 (13. 57%) in the inguinal canal and 48 (17.14%) in the scrotum. There were 277 cases (98.9%) in group A and 3 (1.1%) in group B. Of the 36 undescended testes analyzed 2 (5.6%) were abdominal and 34 (94.4%) were inguinal. There were 26 cases (72.2%) in group A, 8 (22.2%) in group B and 2 in group D. CONCLUSIONS: In fetuses without congenital malformations or epididymal alterations, such as tail disjunction or elongated epididymis, the proximal portion of the gubernaculum was attached to the testis and epididymis in all cases. In undescended testes there was an increased incidence of paratesticular structure malformations accompanied by gubernacular attachment anomalies compared to the testes in normal fetuses.

Ectopic scrotum: a review of the literature and report of a further case

The third case of unilateral ectopic scrotum is reported. There was no associated urinary tract abnormality in contrast to the previously reported cases. The development is described and the literature reviewed (AU)