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Whole-Exome Sequencing Identifies Novel Heterozygous Mutation in RAF1 in Family With Neonatal Testicular Torsion. Urology 2019; 129:60-67. [DOI: 10.1016/j.urology.2019.01.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 12/31/2018] [Accepted: 01/08/2019] [Indexed: 12/30/2022]
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2
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van Gelder MM, van Rooij IA, de Jong-van den Berg LT, Roeleveld N. Teratogenic Mechanisms Associated with Prenatal Medication Exposure. Therapie 2014; 69:13-24. [DOI: 10.2515/therapie/2014003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 10/18/2013] [Indexed: 12/31/2022]
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Acién P, Sánchez del Campo F, Mayol MJ, Acién M. The female gubernaculum: role in the embryology and development of the genital tract and in the possible genesis of malformations. Eur J Obstet Gynecol Reprod Biol 2011; 159:426-32. [DOI: 10.1016/j.ejogrb.2011.07.040] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 07/01/2011] [Accepted: 07/14/2011] [Indexed: 01/14/2023]
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4
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Sadeu JC, Hughes CL, Agarwal S, Foster WG. Alcohol, drugs, caffeine, tobacco, and environmental contaminant exposure: reproductive health consequences and clinical implications. Crit Rev Toxicol 2010; 40:633-52. [PMID: 20662712 DOI: 10.3109/10408444.2010.493552] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Reproductive function and fertility are thought to be compromised by behaviors such as cigarette smoking, substance abuse, and alcohol consumption; however, the strength of these associations are uncertain. Furthermore, the reproductive system is thought to be under attack from exposure to environmental contaminants, particularly those chemicals shown to affect endocrine homeostasis. The relationship between exposure to environmental contaminants and adverse effects on human reproductive health are frequently debated in the scientific literature and these controversies have spread into the lay press drawing increased public and regulatory attention. Therefore, the objective of the present review was to critically evaluate the literature concerning the relationship between lifestyle exposures and adverse effects on fertility as well as examining the evidence for a role of environmental contaminants in the purported decline of semen quality and the pathophysiology of subfertility, polycystic ovarian syndrome, and endometriosis. The authors conclude that whereas cigarette smoking is strongly associated with adverse reproductive outcomes, high-level exposures to other lifestyle factors are only weakly linked with negative fertility impacts. Finally, there is no compelling evidence that environmental contaminants, at concentrations representative of the levels measured in contemporary biomonitoring studies, have any effect, positive or negative, on reproductive health in the general population. Further research using prospective study designs with robust sample sizes are needed to evaluate testable hypotheses that address the relationship between exposure and adverse reproductive health effects.
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Affiliation(s)
- J C Sadeu
- Reproductive Biology Division, Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada
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5
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van Gelder MMHJ, van Rooij IALM, Miller RK, Zielhuis GA, de Jong-van den Berg LTW, Roeleveld N. Teratogenic mechanisms of medical drugs. Hum Reprod Update 2010; 16:378-94. [DOI: 10.1093/humupd/dmp052] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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Foresta C, Zuccarello D, Garolla A, Ferlin A. Role of hormones, genes, and environment in human cryptorchidism. Endocr Rev 2008; 29:560-80. [PMID: 18436703 DOI: 10.1210/er.2007-0042] [Citation(s) in RCA: 152] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cryptorchidism is the most frequent congenital birth defect in male children (2-4% in full-term male births), and it has the potential to impact the health of the human male. In fact, although it is often considered a mild malformation, it represents the best-characterized risk factor for reduced fertility and testicular cancer. Furthermore, some reports have highlighted a significant increase in the prevalence of cryptorchidism over the last few decades. Etiology of cryptorchidism remains for the most part unknown, and cryptorchidism itself might be considered a complex disease. Major regulators of testicular descent from intraabdominal location into the bottom of the scrotum are the Leydig-cell-derived hormones testosterone and insulin-like factor 3. Research on possible genetic causes of cryptorchidism has increased recently. Abundant animal evidence supports a genetic cause, whereas the genetic contribution to human cryptorchidism is being elucidated only recently. Mutations in the gene for insulin-like factor 3 and its receptor and in the androgen receptor gene have been recognized as causes of cryptorchidism in some cases, but some chromosomal alterations, above all the Klinefelter syndrome, are also frequently involved. Environmental factors acting as endocrine disruptors of testicular descent might also contribute to the etiology of cryptorchidism and its increased incidence in recent years. Furthermore, polymorphisms in different genes have recently been investigated as contributing risk factors for cryptorchidism, alone or by influencing susceptibility to endocrine disruptors. Obviously, the interaction of environmental and genetic factors is fundamental, and many aspects have been clarified only recently.
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Affiliation(s)
- Carlo Foresta
- University of Padova, Department of Histology, Microbiology and Medical Biotechnologies, Section of Clinical Pathology and Centre for Male Gamete Cryopreservation, Via Gabelli 63, 35121 Padova, Italy.
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7
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Abstract
Cryptorchidism is failure of one or both testes to descend into the scrotum. Primary fault lies in the testis. We provide a unifying cross-species interpretation of testis descent and urge the use of precise terminology. After differentiation, a testis is relocated to the scrotum in three sequential phases: abdominal translocation, holding a testis near the internal inguinal ring as the abdominal cavity expands away, along with slight downward migration; transinguinal migration, moving a cauda epididymidis and testis through the abdominal wall; and inguinoscrotal migration, moving a s.c. cauda epididymidis and testis to the bottom of the scrotum. The gubernaculum enlarges under stimulation of insulin-like peptide 3, to anchor the testis in place during gradual abdominal translocation. Concurrently, testosterone masculinizes the genitofemoral nerve. Cylindrical downward growth of the peritoneal lining into the gubernaculum forms the vaginal process, cremaster muscle(s) develop within the gubernaculum, and the cranial suspensory ligament regresses (testosterone not obligatory for latter). Transinguinal migration of a testis is rapid, apparently mediated by intra-abdominal pressure. Testosterone is not obligatory for correct inguinoscrotal migration of testes. However, normally testosterone stimulates growth of the vaginal process, secretion of calcitonin gene-related peptide by the genitofemoral nerve to provide directional guidance to the gubernaculum, and then regression of the gubernaculum and constriction of the inguinal canal. Cryptorchidism is more common in companion animals, pigs, or humans (2–12%) than in cattle or sheep (≤1%). Laboratory animals rarely are cryptorchid. In respect to non-scrotal locations, abdominal testes predominate in cats, dogs, and horses. Inguinal testes predominate in rabbits, are common in horses, and occasionally are found in cats and dogs. S.c. testes are found in cattle, cats and dogs, but are most common in humans.
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Affiliation(s)
- R P Amann
- Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, Colorado 80523-1683, USA.
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Veeramachaneni DNR, Amann RP, Jacobson JP. Testis and antler dysgenesis in sitka black-tailed deer on Kodiak Island, Alaska: Sequela of environmental endocrine disruption? ENVIRONMENTAL HEALTH PERSPECTIVES 2006; 114 Suppl 1:51-9. [PMID: 16818246 PMCID: PMC1874179 DOI: 10.1289/ehp.8052] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
It had been observed that many male Sitka black-tailed deer (Odocoileus hemionus sitkensis) on Kodiak Island, Alaska, had abnormal antlers, were cryptorchid, and presented no evidence of hypospadias. We sought to better understand the problem and investigated 171 male deer for phenotypic aberrations and 12 for detailed testicular histopathology. For the low-lying Aliulik Peninsula (AP), 61 of 94 deer were bilateral cryptorchids (BCOs); 70% of these had abnormal antlers. Elsewhere on the Kodiak Archipelago, only 5 of 65 deer were BCOs. All 11 abdominal testes examined had no spermatogenesis but contained abnormalities including carcinoma in situ-like cells, possible precursors of seminoma; Sertoli cell, Leydig cell, and stromal cell tumors; carcinoma and adenoma of rete testis; and microlithiasis or calcifications. Cysts also were evident within the excurrent ducts. Two of 10 scrotal testes contained similar abnormalities, although spermatogenesis was ongoing. We cannot rule out that these abnormalities are linked sequelae of a mutation(s) in a founder animal, followed by transmission over many years and causing high prevalence only on the AP. However, based on lesions observed, we hypothesize that it is more likely that this testis-antler dysgenesis resulted from continuing exposure of pregnant females to an estrogenic environmental agent(s), thereby transforming testicular cells, affecting development of primordial antler pedicles, and blocking transabdominal descent of fetal testes. A browse (e.g., kelp) favored by deer in this locale might carry the putative estrogenic agent(s).
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Affiliation(s)
- D N Rao Veeramachaneni
- Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, Colorado, USA.
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9
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Basrur PK. Disrupted sex differentiation and feminization of man and domestic animals. ENVIRONMENTAL RESEARCH 2006; 100:18-38. [PMID: 16209866 DOI: 10.1016/j.envres.2005.08.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Revised: 08/09/2005] [Accepted: 08/23/2005] [Indexed: 05/04/2023]
Abstract
Genital malformations constitute the most common birth defects in man and domestic animals and occur frequently in males since the participation of many genes is required for sex differentiation to proceed in the male direction. The precise dose, timing, and coordination needed for their expression add to the proneness of various stages in male sex differentiation to external influences. The emerging insight, through the identification of genes involved in the sex differentiation cascade, is that over 85% of sex anomalies in human and domestic animal populations are not attributable to chromosome aberrations or to mutations in a known gene. Since a majority of severely malformed individuals are incapable of reproduction, the high rates of these defects have to be results either of new mutations or of collaboration of environmental factors with genes. Increase in specific malformations in domestic animals often indicates increased concentration of liability genes brought together in the conceptus by inbreeding. However, in human populations where inbreeding is not the norm such increases may reflect environment-induced new mutations or interaction of environmental agents with hormone-sensitive genes. This review summarizes the information currently available on the genetics of major events in male sex differentiation and briefly discusses the collaborative role that environment may play in disrupting different components of this process.
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Affiliation(s)
- Parvathi K Basrur
- Department of Biomedical Sciences, University of Guelph, Guelph, Ont., Canada N1G 2W1
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Bernal-Mañas CM, Morales E, Pastor LM, Pinart E, Bonet S, Rosa PDL, Dolors Briz M, Zuasti A, Ferrer C, Canteras M. Proliferation and apoptosis of spermatogonia in postpuberal boar (Sus domesticus) testes with spontaneous unilateral and bilateral abdominal cryptorchidism. Acta Histochem 2005; 107:365-72. [PMID: 16185749 DOI: 10.1016/j.acthis.2005.07.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 07/12/2005] [Accepted: 07/19/2005] [Indexed: 11/28/2022]
Abstract
Cryptorchidism is a frequent male sexual disorder in mammals, which affects the histology of the tunica propria, interstitial tissue, blood vessels, seminiferous epithelium and testis functioning. In this paper, proliferation and apoptosis were examined in the seminiferous epithelium of both testes from unaffected boars and from boars suffering unilateral and bilateral cryptorchidism. In germ cells, proliferation was studied using the immunohistochemical PCNA technique, and apoptosis was analysed by in situ TUNEL labelling. An index was obtained for the proliferation and apoptosis observed in seminiferous tubules. In abdominal testes the epithelium contained few spermatogonia and Sertoli cells. In the testes of unaffected boars, numerous spermatogonia proliferated, whereas in cryptorchid testes such proliferation was lower and the proliferation/apoptosis ratio diminished. In the unaffected group, the TUNEL-positive germ cells were spermatogonia and spermatocytes in different phases of meiosis. In abdominal testes, the TUNEL-positive germ cells were spermatogonia alone. The apoptosis index of both abdominal and scrotal testes was similar. In conclusion, spontaneous cryptorchid testes showed a lower rate of spermatogonia proliferation in the seminiferous epithelium.
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Affiliation(s)
- Carmen M Bernal-Mañas
- Department of Cell Biology, School of Medicine, University of Murcia, 30100 Murcia, Spain
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Ng SL, Bidarkar SS, Sourial M, Farmer PJ, Donath S, Hutson JM. Gubernacular cell division in different rodent models of cryptorchidism supports indirect androgenic action via the genitofemoral nerve. J Pediatr Surg 2005; 40:434-41. [PMID: 15750944 DOI: 10.1016/j.jpedsurg.2004.10.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE The role of the "gubernaculum" in testicular descent remains controversial. Androgens are proposed to act indirectly by the genitofemoral nerve (GFN) releasing calcitonin gene-related peptide. The authors studied the effects of sensory nerve ablation and androgen blockade on mitosis in the gubernacular tip to determine whether androgens act directly or indirectly. METHODS Five rat models were examined for bromodeoxyuridine (BUdR)-labeling: (i) Sprague-Dawley (SD) rats (controls), (ii) prenatal flutamide-treated rats (75 mg/kg to dams on D16-19 gestation), (iii) neonatal capsaicin-treated rats (50 mg/kg, subcutaneous on day 0), (iv) congenitally cryptorchid transcrotal (TS) rats, and (v) capsaicin-treated TS rats (50 mg/kg, subcutaneous on day 0). Newborn rats were collected at days 0, 2, 4, 6, 8, and 10 (age, n = 5/model, n = 30) and were injected intraperitoneally with 1 mg/kg BUdR, 2 hours before killing. Histological sections of gubernaculum were examined immunohistochemically for BUdR labeling. RESULTS In SD (control) rats, DNA synthesis in the gubernacular tip was high at birth, reached a peak at day 2, and then decreased progressively until day 10. A similar pattern was observed in TS rats. However, quantitatively, the levels were significantly higher. In flutamide-treated rats, DNA synthesis was suppressed until day 6, similar suppression was observed in capsaicin-treated SD, and TS rats until day 4. CONCLUSIONS Flutamide, a competitive androgen receptor blocker, reduces gubernacular mitosis to basal levels until day 6, highlighting the importance of androgen receptor. Excess DNA accumulation in TS rats is consistent with the known excess of GFN fibers and calcitonin gene-related peptide in this mutant. Capsaicin-inhibited mitosis in both day 2 SD and TS rats suggests that the GFN mediates androgen action on early postnatal gubernacular DNA synthesis and growth.
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Affiliation(s)
- Sunt Li Ng
- F. Douglas Stephens Surgical Research Laboratory, Murdoch Children's Research Institute, Parkville, Victoria, 3052, Australia
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Vigueras RM, Reyes G, Moreno-Mendoza N, Merchant-Larios H. Gubernacular fibroblasts express the androgen receptor during testis descent in cryptorchid rats treated with human chorionic gonadotrophin. ACTA ACUST UNITED AC 2004; 32:386-90. [PMID: 15503001 DOI: 10.1007/s00240-004-0408-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2003] [Accepted: 02/11/2004] [Indexed: 10/26/2022]
Abstract
Cryptorchidism was provoked in 3 day old rats treated with 17-beta-estradiol over 30 days to identify the cells that express the androgen receptor (AR) during experimental testis descent in the gubernaculum. In one group of animals, testis descent was induced with human chorionic gonadotrophin (hCG) applied daily for 5 or 10 days. A correlative study using a testosterone radioimmunoassay with electron microscopy and immunocytochemical detection of AR was performed in gubernacula of hCG treated and untreated control animals. The gubernaculum of rats undergoing testes descent showed a dramatic increase in the number of AR-positive cells. These were located in the connective tissue among smooth muscle cells in the gubernacular cord and between striated muscle fibers in the bulb. In both regions, the AR-positive cells were identified as fibroblasts. Several clusters of amorphous material appeared in the extracellular matrix of the connective tissue in hCG treated rats. Our results suggest that testosterone induces the expression of AR in gubernacular fibroblasts which seem to degrade the extracellular matrix during gubernacular involution.
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Klonisch T, Fowler PA, Hombach-Klonisch S. Molecular and genetic regulation of testis descent and external genitalia development. Dev Biol 2004; 270:1-18. [PMID: 15136137 DOI: 10.1016/j.ydbio.2004.02.018] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2003] [Revised: 01/18/2004] [Accepted: 02/17/2004] [Indexed: 12/27/2022]
Abstract
Testicular descent as a prerequisite for the production of mature spermatozoa and normal external genitalia morphogenesis, and therefore facilitating copulation and internal fertilization, are essential developmental steps in reproduction of vertebrate species. Cryptorchidism, the failure of testis descent, and feminization of external genitalia in the male, usually in the form of hypospadias, in which the opening of the urethra occurs along the ventral aspect of the penis, are the most frequent pediatric complications. Thus, elucidating the molecular mechanisms involved in the regulation of testis descent and the formation of external genitalia merits a special focus. Natural and transgenic rodent models have demonstrated both morphogenic processes to be under the control of a plethora of genetic factors with complex time-, space-, and dose-restricted expression pattern. The review elucidates the molecular mechanisms involved in the regulation of testis descent and the formation of external genitalia and, wherever possible, assesses the differences between these rodent animal models and other mammalian species, including human.
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Affiliation(s)
- Thomas Klonisch
- Department of Anatomy and Cell Biology, Medical Faculty, Martin Luther University of Halle-Wittenberg, Halle/Saale, Germany.
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Matsuno Y, Komiyama M, Tobe T, Toyota N, Adachi T, Mori C. Association of testicular undescent induced by prenatal flutamide treatment with thickening of the cremaster muscle in rats. Reprod Med Biol 2003; 2:109-113. [PMID: 29699173 DOI: 10.1046/j.1445-5781.2003.00026.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background and Aims: Previously, in cryptorchid rats, which were induced by prenatal exposure to flutamide, we found a thickening of the cremaster muscle. This study was undertaken to quantify the increase of the cremaster muscle thickness in the cryptorchid rats, and to examine its possible relationship with the proliferation of muscle cells. Methods: To obtain cryptorchid rats, pregnant Wistar rats were subcutaneously injected with flutamide (100 mg/kg per day) during gestational days 16-17. Serial sections of the scrotum, containing the testis and cremaster muscle, were prepared from the control and cryptorchid rats that were 2-6 weeks of age, and stained with hematoxylin-eosin for morphometry, or stained with antibody against the proliferating cell nuclear antigen (PCNA) to analyze the cell proliferation ability. Results: The thickened cremaster muscle was always associated with cryptorchid testis and, in the case of unilateral cryptorchidism, the cremaster muscle of the contralateral (descended testis) side exhibited normal thickness. The average thickness of the affected cremaster muscle was 0.80 and 1.89 mm at 4 and 6 weeks of age, respectively, although that of the normal muscle was 0.28 and 0.33 mm at the same time period, respectively. Conclusion: Our results showed that the cremaster muscle of the cryptorchid rats was significantly thicker than that of the control rats. The immunohistochemical analysis revealed that a thickened cremaster muscle contained many PCNA-positive nuclei even at 4 weeks of age, in contrast to the control, which had only a few positive nuclei. Our present study indicates that continuous proliferation of the muscle cells associated with cryptorchid testis increases the thickness of cremaster cells in rats exposed to flutamide prenatally. (Reprod Med Biol 2003; 2: 109-113).
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Affiliation(s)
| | | | - Toyofusa Tobe
- Urology, Graduate School of Medicine, Chiba University, Chiba
| | - Naoji Toyota
- Department of Social Welfare and Environment, Kumamoto Gakuen University, Kumamoto
| | - Tetsuya Adachi
- Center for Research and Development of Bioresources, Research Institute for Advanced Science and Technology, Osaka Prefecture University, Sakai, Osaka and
| | - Chisato Mori
- Departments of Bioenvironmental Medicine and.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Corporation (JST), Kawaguchi, Japan
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Thonneau PF, Gandia P, Mieusset R, Candia P. Cryptorchidism: incidence, risk factors, and potential role of environment; an update. JOURNAL OF ANDROLOGY 2003; 24:155-62. [PMID: 12634298 DOI: 10.1002/j.1939-4640.2003.tb02654.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Patrick F Thonneau
- Human Fertility Research Group, Urology and Andrology Department, La Grave Hospital, Toulouse, France.
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Foster WG, Hughes CL, Chan S, Platt L. Human developmental exposure to endocrine active compounds. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2002; 12:75-81. [PMID: 21782626 DOI: 10.1016/s1382-6689(02)00025-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Quantification of exposure to environmental contaminants such as endocrine active chemicals (EACs) during critical periods of development, particularly in utero, remains largely unexplored. Therefore, we tested the hypothesis that EACs can be detected and quantified in second trimester human amniotic fluid. Amniotic fluid was obtained from women (n=175) undergoing routine amniocentesis between 14 and 21 weeks gestation. Samples were assayed by gas chromatography/mass spectrometry (GC/MS) for common organochlorine contaminants and dietary phytoestrogens. The DDT metabolite p,p'-DDE was found in approximately 25% of amniotic fluid samples (mean±S.D., 0.15±0.06 ng/ml) whereas the dietary phytoestrogens, genistein and or daidzein were found in 96.2% of samples tested (0.94±0.91 and 1.08±0.91 ng/ml, respectively). Our results demonstrate that: (1) human amniotic fluid is a suitable biological medium to evaluate developmental exposure to EACs, and (2) fetuses are exposed to biologically active levels of EACs in mid pregnancy.
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Affiliation(s)
- Warren G Foster
- Department of Obstetrics & Gynecology, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Obstetrics & Gynecology, McMaster University Medical Center, McMaster University, HSC-3N52D, 1200 Main Street West, Hamilton, Ont., Canada L8N 3Z5
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Yang YG, Toyota N, Tobe T, Matsuno Y, Takano K, Koh KB, Komiyama M, Mori C. Immunohistochemical Changes of Androgen Receptor and Estrogen Receptors .ALPHA. and .BETA. in the Gubernaculum of Cryptorchid Rats during Testicular Descent. Acta Histochem Cytochem 2002. [DOI: 10.1267/ahc.35.281] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Ya-Gai Yang
- Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University
| | - Naoji Toyota
- Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University
| | - Toyofusa Tobe
- Department of Urology, Graduate School of Medicine, Chiba University
| | - Yoshiharu Matsuno
- Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University
| | - Kaiya Takano
- Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University
| | - Kyu-Bom Koh
- Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University
| | - Masatoshi Komiyama
- Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University
| | - Chisato Mori
- Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Corporation (JST)
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Tomboc M, Lee PA, Mitwally MF, Schneck FX, Bellinger M, Witchel SF. Insulin-like 3/relaxin-like factor gene mutations are associated with cryptorchidism. J Clin Endocrinol Metab 2000; 85:4013-8. [PMID: 11095425 DOI: 10.1210/jcem.85.11.6935] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cryptorchidism is a common anomaly of male sexual differentiation. Two phases of testicular descent are recognized, transabdominal and inguinoscrotal. With evidence that androgens and Müllerian inhibitory hormone were not completely responsible for testicular descent, the existence of a third testicular hormone mediating testicular descent was postulated. Insulin-like 3 (INSL3) [also known as relaxin-like factor (RLF) and Leydig insulin-like protein (LEY I-L)] is a member of the insulin/relaxin hormone superfamily that is highly expressed in Leydig cells. The phenotype of transgenic mice with targeted deletion of the Insl3 gene was bilateral cryptorchidism with morphological evidence of abnormal gubernacular development. With this implicit evidence that Insl3 mediates testicular descent in mice, we performed mutation detection analysis of the coding regions of the 2 exon INSL3 gene in genomic DNA samples obtained from 145 formerly cryptorchid patients and 36 adult male controls. Single-strand conformational polymorphism analysis was used for the mutation detection studies. Two mutations, R49X and P69L, and several polymorphisms were identified. Both mutations were located in the connecting peptide region of the protein. The frequency of INSL3/RLF gene mutations as a cause of cryptorchidism is low, because only 2 of 145 (1.4%) formerly cryptorchid patients were found to have mutations.
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Affiliation(s)
- M Tomboc
- Division of Pediatric Endocrinology, Children's Hospital of Pittsburgh, University of Pittsburgh, Pennsylvania 15213, USA
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BARTHOLD JULIASPENCER, KUMASI-RIVERS KANDIS, UPADHYAY JYOTI, SHEKARRIZ BIJAN, IMPERATO-MCGINLEY JULIANNE. TESTICULAR POSITION IN THE ANDROGEN INSENSITIVITY SYNDROME: IMPLICATIONS FOR THE ROLE OF ANDROGENS IN TESTICULAR DESCENT. J Urol 2000. [DOI: 10.1016/s0022-5347(05)67411-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- JULIA SPENCER BARTHOLD
- From the Department of Urology, Children’s Hospital of Michigan and Wayne State University School of Medicine, Detroit, Michigan, and Department of Internal Medicine, Division of Endocrinology and Metabolism, New York Hospital-Cornell University Medical College, New York, New York
| | - KANDIS KUMASI-RIVERS
- From the Department of Urology, Children’s Hospital of Michigan and Wayne State University School of Medicine, Detroit, Michigan, and Department of Internal Medicine, Division of Endocrinology and Metabolism, New York Hospital-Cornell University Medical College, New York, New York
| | - JYOTI UPADHYAY
- From the Department of Urology, Children’s Hospital of Michigan and Wayne State University School of Medicine, Detroit, Michigan, and Department of Internal Medicine, Division of Endocrinology and Metabolism, New York Hospital-Cornell University Medical College, New York, New York
| | - BIJAN SHEKARRIZ
- From the Department of Urology, Children’s Hospital of Michigan and Wayne State University School of Medicine, Detroit, Michigan, and Department of Internal Medicine, Division of Endocrinology and Metabolism, New York Hospital-Cornell University Medical College, New York, New York
| | - JULIANNE IMPERATO-MCGINLEY
- From the Department of Urology, Children’s Hospital of Michigan and Wayne State University School of Medicine, Detroit, Michigan, and Department of Internal Medicine, Division of Endocrinology and Metabolism, New York Hospital-Cornell University Medical College, New York, New York
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TESTICULAR POSITION IN THE ANDROGEN INSENSITIVITY SYNDROME: IMPLICATIONS FOR THE ROLE OF ANDROGENS IN TESTICULAR DESCENT. J Urol 2000. [DOI: 10.1097/00005392-200008000-00072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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23
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Pinart E, Sancho S, Briz MD, Bonet S, Garcia N, Badia E. Ultrastructural study of the boar seminiferous epithelium: changes in cryptorchidism. J Morphol 2000; 244:190-202. [PMID: 10815002 DOI: 10.1002/(sici)1097-4687(200006)244:3<190::aid-jmor4>3.0.co;2-b] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The present study compares the ultrastructural features of Sertoli cells and germ cells between scrotal testes of healthy boars and abdominal testes of unilateral and bilateral cryptorchid boars. In healthy boars, spermatogonia are flat cells lying in close association with the basal lamina. As differentiation progresses, spermatogonia acquire an oval profile and lose their contact with the basal lamina. Spermatocytes are round cells moving from the basal compartment of the seminiferous epithelium to the luminal compartment. Spermatids exhibit complex morphological changes leading to the formation of spermatozoa. Sertoli cells extend from the basal lamina to the tubular lumen. The nucleus encloses fine euchromatin and one or two nucleoli; the nuclear envelope has a few deep infoldings. The lateral cell membranes form junctional specializations that constitute the blood-testis barrier. The cytoplasm encloses smooth endoplasmic reticulum, vesicles, aggregates, and scattered mitochondria. The seminiferous epithelium of abdominal testes from unilateral and bilateral cryptorchid boars contains few spermatogonia with an abnormal appearance; the alteration in germ cell number is more severe in the bilateral disease. In unilateral cryptorchid boars, spermatogonia appear as either large pyramidal cells or roundish cells; in bilateral cryptorchid boars, spermatogonia show roundish profiles and degenerative patterns. Abdominal testes of both unilateral and bilateral cryptorchid boars are constituted by immature Sertoli cells that show abnormal cytoplasmic content, defective development of the blood-testis barrier, and atypical nuclear appearance; in bilateral cryptorchid boars, immature Sertoli cells exhibit degenerative signs. At postpubertal age, unilateral and bilateral cryptorchidism induce total arrest of spermatogenesis at spermatogonial stage as a result of an abnormal differentiation of the Sertoli cells. Moreover, the degeneration of abdominal testes initiates earlier in bilateral cryptorchidism than in unilateral cryptorchidism.
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Affiliation(s)
- E Pinart
- Reproductive Biology Unit, Department of Biology, Faculty of Sciences, University of Girona, Girona, Spain.
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24
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Pinart E, Sancho S, Briz MD, Bonet S, Badia E. Efficiency of the process of meiosis in scrotal testes of healthy boars and unilateral abdominal cryptorchid boars. TERATOLOGY 1999; 60:209-14. [PMID: 10508974 DOI: 10.1002/(sici)1096-9926(199910)60:4<209::aid-tera5>3.0.co;2-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Unilateral abdominal cryptorchidism has usually been correlated with abnormalities in the spermatogenic activity of the scrotal testis. The present study describes the effects of unilateral abdominal cryptorchidism on the meiotic process in scrotal testes from postpubertal boars. The percentage of primary spermatocytes, secondary spermatocytes, and round spermatids was evaluated in testicular smears from scrotal testes of healthy boars and of right-sided unilateral abdominal cryptorchid boars. As compared to the scrotal testes of healthy boars, the scrotal testes of unilateral abdominal cryptorchid boars showed low transformation from primary to secondary spermatocytes (meiosis I), but normal transformation from secondary spermatocytes to round spermatids (meiosis II). The data obtained indicate that spontaneous unilateral abdominal cryptorchidism on the right side induced partial arrest of spermatogenesis at the primary spermatocyte stage that was attributed to anomalies in Sertoli-cell activity. Abnormal paracrine signals from altered Sertoli cells could have resulted in either disturbed mitosis, which led to the formation of spermatocytes with an abnormal DNA content, or abnormalities in the metabolic activity and the organization of the cytoskeleton of primary spermatocytes.
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Affiliation(s)
- E Pinart
- Department of Biology, Faculty of Sciences, University of Girona, 17071 Girona, Spain.
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25
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Barthold JS, Kryger JV, Derusha AM, Duel BP, Jednak R, Skafar DF. Effects of an environmental endocrine disruptor on fetal development, estrogen receptor(alpha) and epidermal growth factor receptor expression in the porcine male genital tract. J Urol 1999; 162:864-71. [PMID: 10458397 DOI: 10.1097/00005392-199909010-00079] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE We studied the effect of a potent reproductive tract toxin, 2,3,7,8-tetrachlorodibenzo-rho-dioxin, on fetal development and expression of estrogen receptor alpha and epidermal growth factor receptor (EGFR) in male swine. MATERIALS AND METHODS Fetal domestic swine and miniswine were injected with 1 microg./kg. dioxin on day 50 of gestation and removed near term (114 days). Germ cell counts were performed on sections of formalin fixed testes. Estrogen receptor a protein, and messenger ribonucleic acid (mRNA) and EGFR mRNA expression were analyzed in frozen tissue using Western blotting and semiquantitative reverse transcriptase polymerase chain reaction. RESULTS Of 15 dioxin exposed male offspring 8 (53%) had genital anomalies, including cryptorchidism in 4, epididymal detachment in 1, epididymal atresia in 1 and vasal dilatation in 3, while 3 of 17 control male swine (18%) had incompletely descended testes (p = 0.06). High intra-abdominal testes were found in 3 of 4 cryptorchid dioxin exposed but no control male swine. Mean germ cell number per tubule was 4.0+/-1.1 and 2.7+/-0.7 in control and dioxin groups, respectively (p = 0.01). Estrogen receptor a protein and mRNA were identified in fetal uterus, testis, gubernaculum and epididymis. Protein levels were 2 to 3-fold higher in dioxin exposed testis, and mRNA levels were significantly lower in gubernaculum and epididymis. EGFR mRNA expression was similar in treated and control testis and epididymis. CONCLUSIONS Preliminary data suggest that dioxin produces cryptorchidism and wolffian duct anomalies in male swine exposed just before mid gestation. Germ cell counts and estrogen receptor alpha mRNA expression in gubernaculum and epididymis were significantly reduced, and estrogen receptor a protein expression in testis appeared to be increased by dioxin exposure. Aberrant regulation of estrogen receptor a expression by dioxin may contribute to reproductive tract anomalies in male fetuses.
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Affiliation(s)
- J S Barthold
- Department of Urology, Children's Hospital of Michigan and Wayne State University School of Medicine, Detroit, USA
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26
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Pinart E, Sancho S, Briz MD, Bonet S, García N. Characterization of the semen quality of postpuberal boars with spontaneous unilateral abdominal cryptorchidism on the right side. Anim Reprod Sci 1999; 55:269-78. [PMID: 10379677 DOI: 10.1016/s0378-4320(99)00022-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In recent studies, we found that the ectopic testis from postpuberal boars with unilateral abdominal cryptorchidism does not produce sperm. Therefore, in these males, the seminal characteristics can be used as indicators of the activity of the scrotal testis and its epididymis and also the accessory glands. The semen quality (ejaculate volume, cell-rich fraction volume, sperm concentration, sperm vitality, sperm motility, sperm morphology and cephalic stability of spermatozoa) was evaluated in healthy postpuberal boars and in postpuberal boars with unilateral abdominal cryptorchidism on the right side. In comparison with the healthy boars, the unilateral abdominal cryptorchid boars showed a significant decrease of the ejaculate volume, sperm concentration and sperm motility. The low sperm concentration indicated that unilateral abdominal cryptorchidism severely impairs the sperm production of the scrotal testis. The decrease of ejaculate volume was attributed to an abnormal activity of the accessory glands. The alterations in sperm motility develop as a result of dysfunctions in the epididymal epithelium and/or the accessory glands. The sperm vitality, sperm morphology and cephalic stability of spermatozoa maintained normal values; therefore, at testicular level, despite the low sperm production, the germ cell differentiation is not disturbed. At epididymal level, the morphological maturation of spermatozoa is not altered.
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Affiliation(s)
- E Pinart
- Department of Biology, Faculty of Sciences, University of Girona, Spain.
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Pinart E, Sancho S, Briz M, Bonet S. Morphologic study of the testes from spontaneous unilateral and bilateral abdominal cryptorchid boars. J Morphol 1999; 239:225-43. [PMID: 10081151 DOI: 10.1002/(sici)1097-4687(199903)239:3<225::aid-jmor1>3.0.co;2-v] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Macroscopical and histological characteristics were examined in both testes from three healthy boars, three boars with unilateral abdominal cryptorchidism on the right side, and three boars with bilateral abdominal cryptorchidism. Abdominal cryptorchidism, unilateral and bilateral, provoked a significant decrease of the weight and volume of the ectopic testes. The scrotal testis of the unilateral cryptorchid boars showed an increase in its volume and weight. Cryptorchidism also induced abnormalities in the histological structure of seminiferous tubules, lamina propria, and interstitial tissue of the abdominal testes. The number of seminiferous tubules decreased; the seminiferous epithelium was constituted by few spermatogonia with an atypical pattern and by abnormal Sertoli cells. The lamina propria showed a variable degree of thickening and collagenization. The interstitial tissue was very developed but displayed a decrease in the Leydig cell population. These abnormalities were more critical in bilateral cryptorchidism than in unilateral cryptorchidism. The scrotal testis of the unilateral cryptorchid boars showed normal appearance, but a decrease of the number of seminiferous tubules was observed. Moreover, the seminiferous tubules showed impaired spermatid maturation. The alterations observed in the abdominal testes of the unilateral and bilateral cryptorchid boars were attributed to defective proliferation and differentiation of Sertoli cells and Leydig cells. The anomalies in the scrotal testis of the unilateral cryptorchid boars were due to disturbances in the Sertoli cell activity.
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Affiliation(s)
- E Pinart
- Department of Biology, Faculty of Sciences, University of Girona, Spain.
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28
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Foster WG. Agents perturbateurs du système endocrinien et développement de l’appareil reproducteur chez le foetus et chez l’enfant : y a-t-il lieu de s’inquiéter? Canadian Journal of Public Health 1998. [DOI: 10.1007/bf03405094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Pinart E, Camps R, Briz MD, Bonet S, Egozcue J. Unilateral spontaneous abdominal cryptorchidism: structural and ultrastructural study of sperm morphology. Anim Reprod Sci 1998; 49:247-68. [PMID: 9558443 DOI: 10.1016/s0378-4320(97)00074-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Sperm morphology of three healthy boars and three boars with spontaneous abdominal cryptorchidism in the right testis has been evaluated by light microscopy. For each boar, two ejaculates have been analysed, corresponding to semen collections at the ages of 6.5 months (first collection) and 8 months (seventh collection). A comparative study of the sperm malformations present in the seventh semen collection between the healthy boars and the unilateral abdominal cryptorchid boars has also been performed by light microscopy. Sperm malformations of the seventh semen collection from the unilateral abdominal cryptorchid boars have been examined by scanning and transmission electron microscopy. The frequency of mature spermatozoa, immature spermatozoa, aberrant spermatozoa and detached heads maintained normals values in the first and the seventh semen collection from the unilateral abdominal cryptorchid boars. The comparative study of sperm abnormalities in the seventh semen collection between the cryptorchid boars and the healthy boars indicated that the unilateral abdominal cryptorchid boars had a significantly higher frequency of primary abnormalities, and a significantly lower frequency of secondary abnormalities. Some primary abnormalities, such as crater defect, knobbed acrosome defect, nuclear crests and abaxial tails were only observed in the unilateral abdominal cryptorchid boars. It was concluded that unilateral abdominal cryptorchidism provokes disturbances in the late stages of spermiogenesis, at testicular level. Alterations in the sperm maturation process at epididymal level were not found.
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Affiliation(s)
- E Pinart
- Department of Biology, Faculty of Sciences, University of Girona, Spain
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30
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Hutson JM, Hasthorpe S, Heyns CF. Anatomical and functional aspects of testicular descent and cryptorchidism. Endocr Rev 1997; 18:259-80. [PMID: 9101140 DOI: 10.1210/edrv.18.2.0298] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- J M Hutson
- F. Douglas Stephens Surgical Laboratory, Royal Children's Hospital Research Foundation, Parkville, Victoria, Australia
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Barthold JS, Mahler HR, Sziszak TJ, Newton BW. Lack of feminization of the cremaster nucleus by prenatal flutamide administration in the rat and pig. J Urol 1996; 156:767-71. [PMID: 8683779 DOI: 10.1097/00005392-199608001-00057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE The sexually dimorphic cremaster nucleus contains motoneurons that project via the genitofemoral nerve and theoretically direct androgen dependent testicular descent. The effects of flutamide on descent and masculinization of the cremaster nucleus were studied in the rat and pig. MATERIALS AND METHODS Flutamide was given to pregnant rats and pigs on days 16 to 22 and 65 to 113 of gestation, respectively. Tissues were perfused and examined at birth (pigs) or at age 30 days (rats). Spinal cords were removed, sectioned and immunohistochemically stained for serotonin (rats) or substance P (pigs) to demarcate the position of the cremaster nucleus and allow the determination of cremaster motoneuron number. RESULTS After exposure to flutamide testes were undescended in 6 of 9 rats and 7 of 10 pigs. Cremaster motoneuron number per nucleus were 288 +/- 22 in control versus 250 +/- 27 in flutamide treated rats, and 165 +/- 28 in control versus 148 +/- 24 in flutamide treated pigs. The decrease in motoneuron number by flutamide was significant in both species (p < 0.02) but it did not approach the levels in female rats (93 +/- 11) and pigs (57 +/- 12). Cremaster motoneuron number did not correlate with testicular position. Porcine undescended testes were associated with a significant increase in mean gubernacular volume. CONCLUSIONS Unlike other sexually dimorphic spinal cord nuclei masculinization of the cremaster nucleus appears to be largely androgen independent and it does not correlate with ipsilateral testicular descent. These data suggest that androgens do not mediate descent of the testes via the efferent limb of the genitofemoral nerve.
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Affiliation(s)
- J S Barthold
- Department of Urology, University of Arkansas for Medical Sciences, Little Rock, USA
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Lack of Feminization of the Cremaster Nucleus by Prenatal Flutamide Administration in the Rat and Pig. J Urol 1996. [DOI: 10.1016/s0022-5347(01)65810-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
At present, we believe that descent of the testes within the human is a complex event mediated by both hormonal and mechanical factors. We hypothesize that descent of the testes occurs as a result of the secretion of an androgen-independent factor from a normal testis (descendin). This paracrine factor is responsible for the rapid proliferation (outgrowth) of the ipsilateral gubernaculum. The development of the gubernaculum results in creating a dilated inguinal canal, the width of which matches the testicular width. Descent of the testes through the inguinal canal is an interplay between abdominal pressure, a patent processus vaginalis, and androgen-induced gubernacular regression. We hypothesize that androgens (under control of an intact hypothalamic pituitary axis) alter the viscoelastic properties of the gubernaculum, reducing the turgidity of the gubernaculum and allowing intra-abdominal pressure to push the testis into the scrotum. Cryptorchidism can therefore result when any one or more of the involved factors malfunction.
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Affiliation(s)
- D A Husmann
- Department of Urology, Mayo Clinic, Rochester, Minnesota 55905, USA
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