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PubMed2004

Histopathological effects of boldenone in cattle.

Histopathology of male cattle previously found positive for béta-boldenone in urine in the Netherlands and in Italy was studied. The animals were derived from practice and several weeks had passed after the finding of béta-boldenone before the animals were examined. The animals consisted of 34 male veal calves and one finishing bull. In the prostate gland hypersecretion, cyst formation (45%) and hyperplasia of the urethral epithelium was observed, in the bulbo-urethral gland similar alterations were present. The testis showed reduced development and degeneration of the germinal epithelium (70%), leading to debris and syncytial cell formation in the lumina. Stromal proliferation was evident. In some animals the liver was sampled and showed periportal fibrosis, bile duct proliferation and sometimes necrosis. The bull also showed degeneration of the germinal epithelium of the testis and absence of sperm production, the prostate gland showed some secretion and had an atrophic appearance. It is concluded that béta-boldenone may lead to degeneration of the germinal epithelium of the testis and hypersecretion and cyst formation in the prostate and bulbo-urethral gland, which alterations may heal in time.

Anabolic Agents↗
PubMed1997

Ontogeny of FSH receptor messenger ribonucleic acid transcripts in relation to FSH secretion and testicular function in sheep.

The role of alternative splicing of the FSH receptor gene in the generation of FSH receptor proteins and testicular function remains an enigma. To address this issue, this investigation was conducted to determine variations in the expression of alternate FSH receptor mRNA transcripts in relation to changes in FSH release, hormone binding activity and testicular function during pubertal development of ram lambs from two genotypes of sheep (Romanov and a cross between Booroola x DLS) with different sexual precocity. Serum 17 beta-estradiol and testosterone concentrations were used as indices of Sertoli cell and testicular function. The results indicated that increases in Sertoli cell and testicular function normally seen during pubertal development are accompanied by age-dependent reductions in concentration of functional FSH receptors, as determined by binding of iodinated FSH to testicular membrane preparations. During the course of these changes, FSH release was either maintained at a steady level in Romanov lambs or it was gradually reduced in the Booroola x DLS cross, thus indicating that the testis had become more responsive to hormonal signal. This acquisition of heightened sensitivity was also associated with contrasting changes in the level of expression of FSH receptor mRNA transcripts. For both geno-types of sheep, 5 distinct species of mRNA transcripts of approximately 1.1, 1.5, 2.0, 2.5 and 6.5 kb were highly expressed from 11 to 22 weeks of age. Amongst these transcripts, the 1.1 kb molecular species was the most abundant. Specific probing for a previously cloned transcript called 151A1 representing the first 4 exons of the FSH receptor gene revealed a paradoxical increase in the level of expression from 11 weeks up to a maximum at 18-22 weeks of age for both genotypes. Collectively, the results indicated that contrasting changes in the production of specific alternatively spliced mRNA transcripts may mediate changes in FSH receptor expression which apparently accounts for the augmentation in sensitivity and function of the testis during pubertal development. Furthermore, the data provide the first important indication that the novel truncated transcript (151A1), which predictably encodes a soluble protein of either intra- or extracellular fate, could be physiologically relevant.

Animals↗
PubMed1985

Role of autoantibodies in the autoimmune response to testis in rainbow trout (Salmo gairdneri).

Rainbow trout, Salmo gairdneri, passively immunized with anti-sperm antibodies developed lesions in the testis characteristic of autoimmune attack. Only animals pre-treated with Freund's complete adjuvant developed these lesions. Investigations into the possible role of autoantibodies during autoimmune attack, carried out in vitro, showed that sperm antibodies were not cytotoxic but did have an opsonic effect on macrophage phagocytosis of sperm in the presence of complement.

Animals↗
PubMed1990

Synthesis and transport of storage proteins by testes in Heliothis virescens.

The synthesis of two storage protein subunits, 76,000-Mr and 82,000-Mr polypeptides, by the testes sheath has been studied in Heliothis virescens. Like fat body, which is the primary site of synthesis for the large extratesticular pool, cells of the testes sheath secrete glycosylated storage proteins assembled into hexamers. The testis sheath differed from fat body in several important respects, including the failure to synthesize an abundant (in the hemolymph) 74,000-Mr storage protein, its relatively reduced expression of the 76,000-Mr polypeptide, and the absence of resorption of storage proteins from the lumen of the testis during pupal development. Cyst cells were also shown to import actively the 82,000-Mr storage protein by pinocytosis of testicular fluid and transfer it to the developing spermatids. Unlike other cell types that sequester storage proteins in the form of cytoplasmic granules, their localization within spermatids was exclusively mitochondrial. These observations suggest that expression of the storage protein genes is regulated tissue specifically and reveal novel pathways for their transport and, perhaps, utilization and function during development.

Animals↗
PubMed2004

Insulin-like 3 signalling in testicular descent.

Undescended testis is one of the most common congenital defects in the newborn boys and the common cause of cryptorchidism. If left untreated, this condition is strongly associated with infertility and drastically increased risk of testicular cancer in adulthood. Testis position in developing males is defined by sexual dimorphic differentiation of two gonadal ligaments, gubernaculum and cranial suspensory ligament. Recent transgenic mouse studies identified testicular hormone insulin-like 3 (INSL3), and its receptor, GREAT/LGR8, as the critical regulators of the gubernacular differentiation. Mutation analysis of the two genes in patients with undescended testis revealed functionally deleterious mutations, which may be responsible for the abnormal phenotype in some of the patients.

Animals↗
PubMed1981

Development of seminal vesicles and coagulating glands in neonatal mice. I. The morphogenetic effects of various hormonal conditions.

Seminal vesicles (SV) and coagulating glands (CG) from neonatal mice 1- to 7-days old were observed in whole mount preparations. Untreated, normal SV developed elaborate epithelial branches beginning on day 3 with secondary branches appearing on day 6. Castration (C), estradiol treatment (E), and castration combined with estradiol treatment (C + E) inhibited the morphogenesis of the epithelial branches. Untreated CG formed solid epithelial stalks that developed lateral epithelial buds on day 3 which attained a complex morphological pattern by day 7. Treatment groups (C, E and C + E) displayed a pattern of retarded growth with few epithelial buds appearing even at day 7. The effects of castration on both SV and CG were reversed by the addition of testosterone. Short term in vitro culture of 1-day-old SV and CG glands in control medium or medium supplemented with estradiol did not exhibit visible growth. Culture of SV and CG glands with testosterone or a piece of testis showed pronounced development.

Animals↗
PubMed1998

Sertoli cell differentiation and Y-chromosome activity: a developmental study of X-linked transgene activity in sex-reversed X/XSxra mouse embryos.

The requirement of Y-chromosome activity for the differentiation of somatic cells and germ cells was studied in the fetal gonads of X/XSxra mouse embryos where the activity of the Sxra fragment of the Y chromosome is influenced by the inactivation and reactivation of the X chromosome. In the interstitial somatic cells, random inactivation of the X and the XSxra chromosomes took place which was revealed by the mosaic expression of an X-linked lacZ transgene. The Sertoli cells, however, displayed a preferentially active XSxra chromosome and the presence of Sxra-active Sertoli cells was associated with the morphogenesis of testicular tubules in the sex-reversed gonads. The activity of the Y-chromosome fragment is therefore necessary for the differentiation of the Sertoli cells which may direct the development of the testis. The expression pattern of the X-linked transgene in X/XSxra germ cells suggests that both the X and the XSxra chromosomes are active. This finding suggests that the presence of Sxra has no impact on the reactivation of the X chromosome in the germ cells and that the X chromosome can be reactivated even though the germ cells are found in the testicular environment. Our results are consistent with the concept that the activity of genes on the XSxra fragment is essential for the differentiation of Sertoli cells and the morphogenesis of the testis, but not for premeiotic differentiation of germ cells in sex-reversed mice.

Animals↗
PubMed2006

The makings of maleness: towards an integrated view of male sexual development.

As the mammalian embryo develops, it must engage one of the two distinct programmes of gene activity, morphogenesis and organogenesis that characterize males and females. In males, sexual development hinges on testis determination and differentiation, but also involves many coordinated transcriptional, signalling and endocrine networks that underpin the masculinization of other organs and tissues, including the brain. Here we bring together current knowledge about these networks, identify gaps in the overall picture, and highlight the known defects that lead to disorders of male sexual development.

Animals↗
PubMed2006

Expression of stress inducible protein 1 (Stip1) in the mouse testis.

Phthalate esters are considered endocrine disruptors that interfere with the endocrine balance and development of the mammalian testis. Mono-2-ethylhexyl phthalate (MEHP), the active metabolite of the ubiquitously used plasticizer di-2-ethylhexyl phthalate (DEHP), acts upon Sertoli cells as initial target. By subtractive cDNA libraries we identified genes deregulated as response to MEHP in primary cultures of mouse Sertoli cells. The expression of mouse stress inducible protein 1 (Stip1) was detected as upregulated as a result of MEHP exposure. Stip1 is a cochaperone protein that is homologous to the human heat shock cognate protein 70 (hsc70)/heat shock protein 90 (hsp90)-organizing protein (Hop). To assess the presence and localization of Stip1 in mouse testis and its potential role in stress defense, we studied the expression pattern of the Stip1 protein by immunohistochemistry and of the mRNA by in situ hybridization. Both the protein and the mRNA of Stip1 were mainly found in the cytoplasm of all types of spermatogonia and spermatocytes up till zygotene, the expression decreased during late pachytene and was very weak in diplotene spermatocytes and round spermatids. Interestingly, this expression pattern resembled the pattern of stress sensitivity of spermatogenic cells in that the most sensitive cell types show the weakest expression of Stip1. This suggests an important role for Stip1 in the ability of germ cells to survive in stress conditions including high temperatures.

Animals↗
PubMed1996

[Cystic ectasia of the rete testis: apropos of a case].

We report a case of a simple testicular cyst developing on the rete testis. Nine cases have been reported in children. In our patient, the cyst was associated with aplasia of the homolateral kidney and termination of the left ureter in the left deferens. According to the literature, the diagnosis is usually fortuitous at histology examination. The cause is probably embryonic malformation. Castration is the therapeutic solution. In our case, simple enucleation allowed preservation of the deferens since the controlateral tree was damaged. There have been no complications with a 6-year follow-up.

Cysts↗
PubMed1991

[Varicocele in children and adolescents. Review of a series of 58 cases].

5 to 25% of male adolescents present with a varicocele; only those cases inducing serious discomfort or affecting the development of the testis require surgical treatment. Nevertheless, the results of surgery are disappointing, with a high recurrence rate. Based on a better knowledge of testicular venous drainage, it appears that conventional high ligation of the spermatic vein (s) might not be sufficient to cure varicocele. Fifty-eight patients were operated upon using four different procedures. Only complete, proximal ligation of all of the visibly dilated veins seems to prevent recurrences with a follow-up of at least one year. However, out of eleven cases treated with this original procedure, one patient, already operated upon twice without success, developed secondary atrophy.

Adolescent↗
PubMedDate not supplied

[Molecular mechanisms in sex determination: from gene regulation to pathology].

Testis determination is the complex process by which the bipotential gonad becomes a normal testis during embryo development. As a consequence, this process leads to sexual differentiation corresponding to the masculinization of both genital track and external genitalia. The whole phenomenon is under genetic control and is particularly driven by the presence of the Y chromosome and by the SRY gene, which acts as the key initiator of the early steps of testis determination. However, many other autosomal genes, present in both males and females, are expressed during testis formation in a gene activation pathway, which is far to be totally elucidated. All these genes act in a dosage-sensitive manner by which quantitative gene abnormalities, due to chromosomal deletions, duplications or mosaicism, may lead to testis determination failure and sex reversal.

Animals↗
PubMed1977

Male rats with inherited insensitivity to androgen show reduced sexual behavior.

Pseudohermaphroditic Stanley-Gumbreck male rats showed infrequent and incomplete copulatory responses to receptive females. Administration of testosterone propionate produced no increase in this behavior. Injections of estradiol and progesterone induced the pseudohermaphrodites to exhibit lordosis when mounted by stimulus males, but feminine responses were no more frequent than those of normal males given the same hormonal treatment. The hypothesis is suggested that early in development sufficient endogenous testis hormone is produced to cause normal desensitization of feminine behavioral mechanisms to estradiol, but that mechanisms for male behavior are not normally sensitized to testosterone.

Animals↗
PubMed1993

Postnatal development of seminiferous tubules in the cat.

Testes were obtained from 20 cats with an age range of 1 day to 1 year. In the neonatal period the seminiferous tubules were widely separated by a well-developed interstitium. Tubular diameter was small and no lumen was observed within the seminiferous tubules. These showed many undifferentiated Sertoli cells with round to ovoid nuclei and only one or two spermatogonia, usually centrally situated. From 2 to 4-5 months the interstitium was sparse, tubular diameters were increased and the morphology of the seminiferous tubules was very similar to that in the neonatal period (< 2 months). From 5 to 7 months, tubular diameters were larger, a lumen was observed, the seminiferous epithelium began to assume its characteristic stratification and the blood testis barrier was developed. From 8 months of age spermatogenesis was fully established.

Animals↗
PubMed1990

[Varicocele in childhood and adolescence. Evaluation apropos of a series of 58 cases].

5 to 25% of the male adolescents present with a varicocele; only those cases inducing serious discomfort or affecting the development of the testis require surgical treatment. Nevertheless the results of surgery are disappointing with a high recurrence rate. Based on a better knowledge of the testicular venous drainage, it appears that the conventional high ligation of the spermatic vein(s) might not be sufficient to cure the varicocele, fifty-eight patients were operated upon using four different procedures. Only a complete and proximal ligation of all of the visibly dilated veins seems to prevent recurrences with a follow-up of at least one year. However, out of eleven cases treated with this original procedure, one patient, already operated upon twice without success, developed secondary atrophy.

Adolescent↗
PubMedDate not supplied

[Nonpalpable testis: current diagnostic and therapeutic trends].

Management of the nonpalpable testis often represent a significant diagnostic and therapeutic challenge for the pediatric surgeon. A variety of imaging studies may locate nonpalpable testis and include ultrasound, CT, MRI, gonadal vasography, and herniography, but none is completely reliable in locating a gonad or proving its absence. Laparoscopy has the advantage of great reliability in locating testes or proving their absence and can be coupled with surgical management; the laparoscopic findings determine the subsequent operative steps. Accurate knowledge of testis location facilitates development of an appropriate surgical strategy either laparoscopic or laparoscopic-assisted or open procedure. The Authors report their preliminary experience with laparoscopy in 30 patients (age range 2-5 years) with 34 nonpalpable testes: 18 testes were intraabdominal, 7 canalicular, 9 atrophic or absent. Out of the 18 intraabdominal testes 2 patients underwent orchiectomy (very small testes), 1 patient testis detorsion and 15 internal spermatic vessels clipping and cutting (first step of staging Fowler-Stephens orchidopexy). At the moment 8 patients, after a 8-10 months interval, underwent second staged vas-based orchidopexy with good results as judged by size and throphism of the relocated testes. An inguinal exploration has been made in 7 patients: 4 orchiectomy (hypo-atrophic testis), 3 standard orchidopexy. In 9 patients the testis were absent. In order to have a good-sized adolescent scrotal pouch, insertion of an infant-size testicular prosthesis is recommended for children with a vanishing or absent testis, if the parents agree.

Algorithms↗
PubMed2002

Response of the amphibian tadpole (Xenopus laevis) to atrazine during sexual differentiation of the testis.

Xenopus laevis tadpoles were exposed for 48 h during sexual differentiation to atrazine at 21 microg/L under static laboratory conditions at 21+/-0.5 degrees C. After this exposure period, tadpoles were fixed and the kidney-gonad complex was microdissected. Quantitative histological analysis of the gonad revealed a 57% reduction in testicular volume among atrazine-exposed tadpoles. In addition, primary spermatogonial cell nests that represent germ cells for the life of the organism were reduced by 70%. Nursing cells, which provide nutritive support for the developing germ cells, had declined by 74%. Testicular resorption was observed among 70% and aplasia or failure of full development of the testis was recorded in 10% of the atrazine-exposed tadpoles. Because cell nests represent the pool of primordial germ cells for the reproductive life of the organism, the combined reduction in spermatogonial cell nests and nursing cells suggest that a pulse exposure to 21 microg/L of atrazine during sexual differentiation could significantly reduce reproduction during the reproductive life of these animals.

Animals↗
PubMed1984

Further studies on the toxicology of the glycol ethers with emphasis on rapid screening and hazard assessment.

The discovery that ethylene glycol monomethyl ether (EGME) could affect the testis and the developing fetus in laboratory animals prompted further work to understand the effect of EGME and to examine additional glycol ethers to see if they showed EGME's reprotoxicity. Propylene glycol monomethyl ether (PGME) was shown not to cause testicular atrophy or to affect the development of rats at 600 ppm by inhalation, whereas EGME caused testicular atrophy at 300 ppm and showed teratogenic potential at 100 ppm. Diethylene glycol monomethyl ether (diEGME) was found to show no teratogenic potential when administered subcutaneously in rats at up to 1000 microL/kg, whereas EGME had effects at 40 microL/kg. EGME has been shown to cause effects on the testis in rats after a single exposure to 600 ppm or above for 4 hr. The effects can be seen as little as 24 hr after exposure. Ethylene glycol monoethyl ether (EGEE) also causes a reduction in testicular weight following a single exposure to saturated vapor for 3 hr (17 mg/l), but ethylene glycol monoisopropyl ether (EGPE) at 15 mg/l and ethylene glycol monobutyl ether (EGBE) at 4 mg/l showed no effect on the testis.

Animals↗