Role of Gubernaculum testis inervation during the process of testicular migration in human fetuses.

PURPOSE: The gubernaculum seems to be the most important anatomical structure in the testicular migration process. The objective of this paper is to review current literature regarding the role of gubernaculum testis nerves in testicular migration. We conducted a comprehensive literature review about the gubernaculum testis innervation. A PubMed database search was performed in April 2024, focusing on gubernaculum testis and cryptorchidism and genitofemoral nerve (GFN) and calcitonin gene-related peptide (CGRP) gene. The gubernaculum has its own nerve supply, the GFN, descending on the anteromedial surface of the psoas muscle from L1-L2 segments. The second phase of testicular descent is regulated by androgens and CGRP, released from the sensory nucleus of the GFN. The GFN doesn't directly play a role in testicular migration but there is a theory that shows a regulatory function of this nerve in hormonal action during this process. The gubernaculum testis has important structural alterations during the testicular migration and the genitofemoral nerve and CGRP gene are of great importance in this process. The genitofemoral nerve provides motor innervation to the cremaster muscle and gubernaculum, which helps regulate the position of the testes within the scrotum.

Histogenesis of the Gubernaculum During Testis Descent in the Goat Fetus (Capra marghoz) / Histogénesis del Gubernaculum Durante el Descenso Testicular en el Feto de Cabra (Capra marghoz)

SUMMARY: Testicular descent is a complex process that only occurs in mammals. The role of the gubernaculum during testicular descent has been explained mainly by its capacity for dilatation and contraction. This study tried to investigate the changes in the structure of the fibers and cells of the gubernaculum in different age levels of testicular descent in goat fetuses. Embryo samples were collected and grouped in such a way that 60 male goat fetuses were obtained from 100 pregnant does (Capra marghoz). The samples were classified based on the average length (CRL) of the used embryos into 6 age groups. Tissues of the gubernaculum were stained using Masson's Trichrome method to observe collagen fibers under light microscopy. In the present study, growth and orientation of collagen fibers of gubernaculum were observed from the age of 51 days in a manner that the arrangement and order of fibroblasts and collagens to be associated with the onset of testicular migration order and collagen fibers until the end of the third month. Further, changes in the cell arrays and strings were observed after the age of 111 days in such a way that near the birth date, the gubernaculum converted into atrophy tissue. It can be said that from the beginning of the period of testicular descent until its completion, the tissue of the gubernaculum undergoes cellular changes, such as deformation and increase and secretion in connective fibers.

El descenso testicular es un proceso complejo que solo ocurre en los mamíferos. El papel del gubernaculum durante este proceso se ha explicado principalmente por su capacidad de dilatarse y contraerse. En este trabajo, se investigaron los cambios en la estructura de las fibras y células del gubernaculum en diferentes etapas del descenso testicular y edades en fetos de cabra. Se recolectaron muestras de embriones, agrupándose de manera que se obtuvieron 60 fetos de macho cabrío a partir de 100 hembras preñadas (Capra marghoz). Las muestras se clasificaron según la longitud media (CRL) de los embriones utilizados, dividiéndose en seis grupos de edad. Los tejidos del gubernaculum se tiñeron utilizando la técnica de Tricrómico de Masson para observar las fibras de colágeno bajo microscopía óptica. En el presente estudio, se observó el crecimiento y la orientación de las fibras colágenas del gubernaculum a partir de los 51 días de edad. La disposición y el orden de los fibroblastos y colágeno se asociaron con el inicio de la migración testicular, observándose las fibras colágenas hasta el final del tercer mes. Además, se detectaron cambios en las matrices y cadenas de células después de los 111 días de edad. Cerca de la fecha de nacimiento, el gubernaculum se convirtió en tejido atrofiado. En conclusión, desde el inicio hasta la finalización del período de descenso testicular, el tejido del gubernaculum sufre cambios celulares, como deformación y aumento de secreción en las fibras conectivas.

Role of Gubernaculum testis inervation during the process of testicular migration in human fetuses

ABSTRACT Purpose: The gubernaculum seems to be the most important anatomical structure in the testicular migration process. The objective of this paper is to review current literature regarding the role of gubernaculum testis nerves in testicular migration. We conducted a comprehensive literature review about the gubernaculum testis innervation. A PubMed database search was performed in April 2024, focusing on gubernaculum testis and cryptorchidism and genitofemoral nerve (GFN) and calcitonin gene-related peptide (CGRP) gene. The gubernaculum has its own nerve supply, the GFN, descending on the anteromedial surface of the psoas muscle from L1-L2 segments. The second phase of testicular descent is regulated by androgens and CGRP, released from the sensory nucleus of the GFN. The GFN doesn't directly play a role in testicular migration but there is a theory that shows a regulatory function of this nerve in hormonal action during this process. The gubernaculum testis has important structural alterations during the testicular migration and the genitofemoral nerve and CGRP gene are of great importance in this process. The genitofemoral nerve provides motor innervation to the cremaster muscle and gubernaculum, which helps regulate the position of the testes within the scrotum.

Abdominal testicular vessel distribution in human fetuses - basis for Fowler-Stephens surgery

ABSTRACT Purpose: To analyze the histology and distribution of abdominal testicular vessels in human fetuses Patients and Methods: We studied 19 fetuses (34 testes) ranging in age from 12 to 19 weeks post-conception. The fetuses were evaluated regarding crown-rump length (CRL), total length (TL) and body weight immediately before dissection. Each testis was dissected and embedded in paraffin, from which 5 µm thick sections were obtained and stained with Masson's trichrome and Anti-CD31 antibody to quantify the vessels. The stereological analysis was carried out with the Image Pro and Image J programs, using a grid to determine volumetric densities (Vv). Means were statistically compared using the unpaired T-test (p<0.05). Results: The fetuses presented mean weight of 222.5g, mean CRL of 15.3 cm and mean TL of 23.2 cm. All testes were in the abdominal position. The mean percentage of vessels (Vv) in the upper portion of the testis was 7.6% (4.6 to 15%) and in the lower portion the mean was 5.11% (2.3 to 9.8%), with a significant difference (p=0.0001). In the analysis between the upper portion of the right and left testes (p=0.99) and in the analysis of the lower portion of the right and left testes (p=0.83), we did not observe significant differences. Conclusion: The upper portion of the abdominal testis in human fetuses had a higher concentration of vessels than the lower portion. These results suggest that manipulation of the lower end of the testis during Fowler-Stephens surgery should be avoided in order to preserve the collateral circulation.

Abdominal testicular vessel distribution in human fetuses - basis for fowler-Stephens surgery.

PURPOSE: To analyze the histology and distribution of abdominal testicular vessels in human fetuses Patients and Methods: We studied 19 fetuses (34 testes) ranging in age from 12 to 19 weeks post-conception. The fetuses were evaluated regarding crown-rump length (CRL), total length (TL) and body weight immediately before dissection. Each testis was dissected and embedded in paraffin, from which 5 µm thick sections were obtained and stained with Masson's trichrome and Anti-CD31 antibody to quantify the vessels. The stereological analysis was carried out with the Image Pro and Image J programs, using a grid to determine volumetric densities (Vv). Means were statistically compared using the unpaired T-test (p<0.05). RESULTS: The fetuses presented mean weight of 222.5g, mean CRL of 15.3 cm and mean TL of 23.2 cm. All testes were in the abdominal position. The mean percentage of vessels (Vv) in the upper portion of the testis was 7.6% (4.6 to 15%) and in the lower portion the mean was 5.11% (2.3 to 9.8%), with a significant difference (p=0.0001). In the analysis between the upper portion of the right and left testes (p=0.99) and in the analysis of the lower portion of the right and left testes (p=0.83), we did not observe significant differences. CONCLUSION: The upper portion of the abdominal testis in human fetuses had a higher concentration of vessels than the lower portion. These results suggest that manipulation of the lower end of the testis during Fowler-Stephens surgery should be avoided in order to preserve the collateral circulation.

Inguinoscrotal stage of testicular descent: analysis in 217 human fetuses.

BACKGROUND: Testicular descent is a complex process of relevant importance for the comprehension of cryptorchidism. Studies about the inguinoscrotal stage of testicular migration correlating the testicular position with fetal parameters are rare in the literature. Our hypothesis is that the transition of the testis by the inguinal canal is a very fast process and occurs at the end of the third gestational trimester. AIM: To analyze the inguinoscrotal stage of testicular descent during the human fetal period. STUDY DESIGN: This is an observational study in human fetuses. We studied 217 human male fetuses ranging from 10 to 35 weeks postconception (WPC). The fetuses were well preserved and evaluated regarding crown-rump length (CRL) and body weight before dissection. 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 being inside the scrotum. Means were statistically compared using the unpaired t-test (P < 0.05). RESULTS: Of the 434 testes, 329 (75.8%) were abdominal, 48 (11.05%) were inguinal, and 57 (13.13%) were scrotal. The first case of inguinal testis was observed in a fetus with 17 WPC, 203 g, and 15 cm CRL. The 48 inguinal testes were observed in 29 fetuses (13.36%), aged between 17 and 29 WPC, weighing between 203 and 1220 g, and with CRL between 15 and 27.5 cm. Of the 29 fetuses with inguinal testes, 23 (79.32%) were aged between 20 and 26 WPC; 3 (10.34%) had 17 WPC; and 3 (10.34%) had more than 26 WPC. All the fetuses with more than 30 WPC had testes in the scrotum. We did not observe fetuses less than 17 WPC with the testes in the canal. DISCUSSION: We found that all fetuses with more than 30 WPC had the testes located in the scrotum and that in fetuses between 17 WPC and 25 WPC, 38 testes (8.7% of the sample) were situated in the canal and only 1 testis in a fetus with 25 WPC was located in the scrotum, showing that the second stage of testicular migration through the inguinal canal rarely occurs before the 20th WPC. CONCLUSION: The inguinoscrotal stage of testicular descent is a fast process, observed only in 13% of the fetuses and occurring with more intensity between 20 and 26 WPC.

Mandibular Regional Odontodysplasia in an 8-year-old Boy showing Teeth Disorders, Gubernaculum Tracts, and Altered Bone Fractal Pattern.

Regional odontodysplasia (RO) is a rare nonhereditary developmental condition usually affecting maxilla and female patients. A few number of articles have used the cone beam computed tomography (CBCT) to describe imaging findings in RO. Thus, this article aims to report unusual imaging findings in a Brazilian child who presented with mandibular RO. A healthy 8-year-old boy was referred for evaluation of an anterior mandibular gingival enlargement. Radiographically, all right mandibular teeth showed wide pulp chambers and shortened roots with thin dentinal walls and open apices, featuring a "ghost teeth" appearance, which indicated a diagnosis of RO. Missing teeth and altered radiopacity were observed. Cone beam computed tomography provided great insight into RO, allowing to identify gubernaculum tracts (GTs) associated with RO teeth. Fractal analysis of the bone surrounding RO teeth revealed an altered trabecular pattern. CLINICAL SIGNIFICANCE: This case describes a rare developmental teeth-related pathology in a boy who showed unusual features on imaging exams. The CBCT provided the observation of RO tooth-related GTs, probably a new finding added to the international literature regarding RO, as well as the pulp chamber volume characterization of an affected tooth not published yet. In addition, it was observed an altered fractal pattern of the mandibular bone adjacent to RO teeth, which has not been described to date.How to cite this article: de Sa Cavalcante D, Fonteles CSR, Ribeiro TR, Kurita LM, Pimenta AVM, Carvalho FSR, Costa FWG. Mandibular Regional Odontodysplasia in an 8-year-old Boy showing Teeth Disorders, Gubernaculum Tracts, and Altered Bone Fractal Pattern. Int J Clin Pediatr Dent 2018;11(2):128-134.

Developmental changes in the gubernaculum and anogenital distance of male rat offspring exposed in utero to WIN 55, 212-2 as a candidate of the endocannabinoid system

Cannabinoids can inhibit the release of androgens locally or centrally. For this reason, this study was designed to assess the effect of WIN 55, 212-2, a CB1 receptor agonist, on gubernacular development histologically. Sprague-Dawley female rats were time-mated and divided into treatment and control groups. For prenatal exposures, the groups received injections subcutaneously of 0.5 mg/kg WIN 55, 212-2 (WIN) or vehicle on gestational days 13.520.5. Five to 13 male offspring were collected at time points E19 (embryonic), P0 (postnatal), P2, and P8. The body weight and anogenital distance (AGD) of postnatal male pups were recorded at birth. The inguino-perineal region of all the samples after fixing in 4% paraformaldehyde were sectioned oblique-sagittally and stained with Hematoxilin and Eosin (HE) or Masson's trichrome. Measured Factors in this study were based on previous studies and included gubernacular cone height (GCH), gubernacular cone width (GCW), distance from gubernaculum to scrotum (G-S), and pubic symphysis-to-anus distance (PS-A). The former two factors were measured bilaterally and the latter two only on the left side. The gubernaculum at P0 appeared more bulky than that of controls. Failure of eversion at P2 and remaining bulb of gubernaculum at P8 were important findings in WIN-treated group. The mean distance from gubernaculum to scrotum increased significantly only atP2 compared to controls. AGD as a bioassay of fetal androgen action also showed a significant 16% reduction as compared with the control group at birth. These data propose that prenatal exposure to WIN can affect gubernacular development probably due to androgen-disruptive action.

Developmental changes in the gubernaculum and anogenital distance of male rat offspring exposed in utero to WIN 55, 212-2 as a candidate of the endocannabinoid system

Cannabinoids can inhibit the release of androgens locally or centrally. For this reason, this study was designed to assess the effect of WIN 55, 212-2, a CB1 receptor agonist, on gubernacular development histologically. Sprague-Dawley female rats were time-mated and divided into treatment and control groups. For prenatal exposures, the groups received injections subcutaneously of 0.5 mg/kg WIN 55, 212-2 (WIN) or vehicle on gestational days 13.520.5. Five to 13 male offspring were collected at time points E19 (embryonic), P0 (postnatal), P2, and P8. The body weight and anogenital distance (AGD) of postnatal male pups were recorded at birth. The inguino-perineal region of all the samples after fixing in 4% paraformaldehyde were sectioned oblique-sagittally and stained with Hematoxilin and Eosin (HE) or Masson's trichrome. Measured Factors in this study were based on previous studies and included gubernacular cone height (GCH), gubernacular cone width (GCW), distance from gubernaculum to scrotum (G-S), and pubic symphysis-to-anus distance (PS-A). The former two factors were measured bilaterally and the latter two only on the left side. The gubernaculum at P0 appeared more bulky than that of controls. Failure of eversion at P2 and remaining bulb of gubernaculum at P8 were important findings in WIN-treated group. The mean distance from gubernaculum to scrotum increased significantly only atP2 compared to controls. AGD as a bioassay of fetal androgen action also showed a significant 16% reduction as compared with the control group at birth. These data propose that prenatal exposure to WIN can affect gubernacular development probably due to androgen-disruptive action.(AU)

Is there a trans-abdominal testicular descent during the second gestational trimester? Study in human fetuses between 13 and 23 weeks post conception

ABSTRACT Objectives To confirm if a real inner descend of testis occurs, correlating the testicular position with fetal parameters and analyzing the position of the testes relative to the internal ring. Material and Methods Twenty nine human fetuses between 13 and 23 weeks post conception (WPC) were studied. The fetuses were carefully dissected with the aid of a stereoscopic lens with 16/25X magnification and testicular position observed. With the aid of a digital pachymeter the distance between the lower pole of the kidney and the upper extremity of the testis (DK-T) was measured to show the position of the testis. During the dissection we also indicated the position of the testes relative to the internal ring. Means were statistically compared using simple linear regression and the paired T-test. Results The 58 testes had abdominal position. The DK-T in the right side measured between 0.17 and 1.82cm (mean=0.79cm) and in the left side it was between 0.12 and 1.84cm (mean=0.87cm), without statistically differences (p=0.0557). The linear regression analysis indicated that DK-T in both sides correlated significantly and positively with fetal age. All fetuses with more than 20 WPC, heavier than 350g and with CRL over 22cm had a greater distance than the average DK-T. We xobserved that the 58 testis remains adjacent to the internal ring throughout the period studied. Conclusions The testes remains adjacent to the internal ring throughout the period studied, indicating that there is no real trans-abdominal testicular descent during the second gestational trimester.

Anatomical Study on the Descent of Testis in Prenatal Goat (Capra hircus) / Estudio Anatómico del Descenso Testicular Prenatal en la Cabra (Capra hircus)

A study was conducted on 70 embryo/ foetii of goats to observe the descent of testis. These foetii were grouped into I (0-30 days), II (31-60 days), III (61-90 days), IV (91-120days) and V (121 days up to term, having 14 embryos/ foetii in each group. The genital ridge was observed at 1.2cm CRL (23 day) on the ventromedial aspect of mesonephros. At 42nd day, the genital ridge developed into cylindrical structure, the testis, located in the middle of metanephros. The abdominal migration was completed upto 88th day. The testes were situated in the inguinal canal from 89th to 95th day. From 90th day onward, scrotal migration had been observed, however the testis did not reach the base of the scrotum up to term. During the descent of testis, a peritoneal fold detached from the caudal end of the gonad and extended up-to the abdominal floor on 42nd day, known as gubernaculum. In the initial stages of pregnancy it was thin, whitish, jelly like. On 70th day it was enveloped by processus vaginalis. In group V, it became hardened, longer and cord like.

Para observar el descenso de los testículos se realizó un estudio en 70 embriones/fetos de cabra. Estos fetos se agruparon en 5 grupos: I (0-30 días), II (31-60 días), III (61-90 días), IV (91 120 días) y V (121 días hasta término, con 14 embriones / fetos en cada grupo. La cresta genital se observó a 1,2cm CRL (23 días) en la cara ventromedial del mesonefros. En el día 42 día, la cresta genital se convirtió en estructura cilíndrica y los testículos se encontraban en el centro del metanefros. La migración abdominal se completó en 88 días. Los testículos están situados en el canal inguinal entre los 89 y 95 días. Del día 90 en adelante, se observó la migración escrotal, sin embargo, el testículo no llegó a la base del escroto hasta el término del desarrollo. Durante el descenso de los testículos, a los 42 días, un pliegue peritoneal (gubernaculum testis) separado del extremo caudal de la gónada, se extendió hacia el suelo-abdominal. En las etapas iniciales de la preñez la gónada era delgada, blanquecina, gelatinosa. En el día 70 el testículo fue envuelto por el proceso vaginal. En el grupo V, el testículo se había endurecido y alargado asemejándose a una cuerda.