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1.
Expression of the protein DDX4/MVH, or VASA, has been reported in germ cells of several species. The main objectives of this study were to (i) investigate VASA expression patterns in testicular cells of stallions at two different reproductive stages (pre‐pubertal and post‐pubertal) and (ii) evaluate the use of VASA antibody as a molecular marker for single germ cells from stallions. Testicular tissues were obtained from stallions and categorized as pre‐pubertal and post‐pubertal based on the formation of lumen and status of spermatogenesis on the cross section of seminiferous tubules. The results of Western blot showed a VASA protein band located at 76 kDa, indicating that the rabbit antibody has a cross‐reactivity with horse testicular tissues. The result of immunolabelling showed that VASA was expressed in the cytoplasm of spermatogonia at both reproductive stages and in spermatocytes and round spermatids at the post‐pubertal stage. GATA4‐positive Sertoli cells and Leydig cells located in the interstitial space were not immunolabelled with VASA. These results suggest that VASA can be utilized as a molecular marker for germ cells of stallions at pre‐pubertal and post‐pubertal stages. Interestingly, immunolabelling intensity was significantly higher in pachytene spermatocytes compared to spermatogonia and round spermatid. VASA antibody was also effective for staining of single germ cell preparations. In conclusion, VASA protein expression can be used as a marker for identification of spermatogonia, spermatocytes and round spermatids in testicular tissues of stallions.  相似文献   

2.
The insulin‐like growth factor‐I (IGF‐I) is a key regulator of reproductive functions. IGF‐I actions are primarily mediated by IGF‐IR. The main objective of this research was to evaluate the presence of IGF‐I and IGF‐I Receptor (IGF‐IR) in stallion testicular tissue. The hypotheses of this study were (i) IGF‐I and IGF‐IR are present in stallion testicular cells including Leydig, Sertoli, and developing germ cells, and (ii) the immunolabelling of IGF‐I and IGF‐IR varies with age. Testicular tissues from groups of 4 stallions in different developmental ages were used. Rabbit anti‐human polyclonal antibodies against IGF‐I and IGF‐IR were used as primary antibodies for immunohistochemistry and Western blot. At the pre‐pubertal and pubertal stages, IGF‐I immunolabelling was present in spermatogonia and Leydig cells. At post‐pubertal, adult and aged stages, immunolabelling of IGF‐I was observed in spermatogenic cells (spermatogonia, spermatocyte, spermatid, and spermatozoa) and Leydig cells. Immunolabelling of IGF‐IR was observed in spermatogonia and Leydig cells at the pre‐pubertal stage. The immunolabelling becomes stronger as the age of animals advance through the post‐pubertal stage. Strong immunolabelling of IGF‐IR was observed in spermatogonia and Leydig cells at post‐puberty, adult and aged stallions; and faint labelling was seen in spermatocytes at these ages. Immunolabelling of IGF‐I and IGF‐IR was not observed in Sertoli cells. In conclusion, IGF‐I is localized in equine spermatogenic and Leydig cells, and IGF‐IR is present in spermatogonia, spermatocytes and Leydig cells, suggesting that the IGF‐I may be involved in equine spermatogenesis and Leydig cell function as a paracrine/autocrine factor.  相似文献   

3.
The current report aimed to characterize plasma anti‐Müllerian hormone (AMH) in bovine male pseudohermaphroditism. The blood AMH concentration in a Japanese Black male pseudohermaphrodite calf was compared with pre‐ and post‐pubertal male and female calves and castrated calves. The concentration in the case was higher than in post‐pubertal males, castrated males, and pre‐ and post‐pubertal female calves (p < .05), but similar to that in pre‐pubertal male calves. After extraction of the testes, the concentration in the case dropped to a certain extent. The extracted testes expressed AMH, as detected by immunohistochemistry. This study is the first to show the characterization of AMH in a male pseudohermaphrodite calf. AMH levels in peripheral blood might be useful to diagnose male pseudohermaphroditism in cattle.  相似文献   

4.
5.
旨在克隆犏牛蛋白磷酸酶1调节亚基11(protein phosphatase 1 regulatory subunit 11,PPP1R11)基因,分析其在不同发育阶段睾丸中的表达与定位,为解析其在雄性生殖中的功能机制提供理论依据.本研究采集成年犏牛睾丸、附睾、心、肝、脾、肺、肾、大肠、小肠、胃、肌肉和脂肪组织(n=3...  相似文献   

6.
In spite of widespread application of flutamide in the endocrine therapies of young and adult patients, the side effects of this antiandrogen on spermatogenesis and germ‐cell morphology remain unclear. This study evaluates the short‐term androgen blockage effect induced by the administration of flutamide to the testes of pubertal (30‐day old) and adult (65‐ and 135‐day old) guinea pigs, with an emphasis on ultrastructural alterations of main cell types. The testes removed after 10 days of treatment with either a non‐steroidal antiandrogen, flutamide (10 mg/kg of body weight) or a pharmacological vehicle alone were processed for histological, quantitative and ultrastructural analysis. In pubertal animals, flutamide androgenic blockage induces spermatogonial differentiation and accelerates testes maturation, causing degeneration and detachment of primary spermatocytes and round spermatids, which are subsequently found in great quantities in the epididymis caput. In post‐pubertal and adult guinea pigs, in addition to causing germ‐cell degeneration, especially in primary spermatocytes, and leading to the premature detachment of spherical spermatids, the antiandrogen treatment increased the relative volume of Leydig cells. In addition, ultrastructural evaluation indicated that irrespective of age antiandrogen treatment causes an increase in frequency of organelles involved with steroid hormone synthesis in the Leydig cells and a dramatic accumulation of myelin figures in their cytoplasm and, to a larger degree, in Sertoli cells. In conclusion, the transient exposition of the guinea pigs to flutamide, at all postnatal ages causes some degenerative lesions including severe premature detachment of spermatids and accumulation of myelin bodies in Leydig and Sertoli cells, compromising, at least temporarily, the spermatogenesis.  相似文献   

7.
Thirty-four pairs of testes from wild adult raccoon dogs (Nyctereutes procyonoides) were obtained between September 2000 and May 2003. The cellular localization of the inhibin alpha and inhibin/activin (betaA and betaB) subunits in wild raccoon dog testes was investigated. The testicular weight and size and seminiferous tubule diameters were measured. There were marked seasonal variations in testicular weight and size and seminiferous tubule diameters, with values relatively low in September and high in March. Spermatogonia and primary spermatocytes were observed in September, and spermatogonia, spermatocytes, and round spermatids were present in January. All types of spermatogenic cells, including mature spermatozoa, were found in March, indicating that the breeding season is around March in Japan. Thereafter, spermatogonia and degenerating spermatocytes were observed in April. The sections of testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against porcine inhibin alpha, inhibin/activin betaA and inhibin/activin betaB. The inhibin alpha and inhibin/activin (betaA and betaB) subunits were only expressed in Leydig cells in September. On the other hand, the inhibin alpha, betaA, and betaB subunits were observed in Leydig cells and Sertoli cells, but not in germ cells, in March. These results suggest that the testes of wild raccoon dogs have the ability to synthesize inhibins, and the cellular localization of inhibin/activin subunits showed season-related changes in the breeding and non-breeding seasons.  相似文献   

8.
Mammalian spermatogenesis involves highly regulated temporal and spatial dynamics, carefully controlled by several signalling processes. Retinoic acid (RA) signalling could have a critical role in spermatogenesis by promoting spermatogonia differentiation, adhesion of germ cells to Sertoli cells, and release of mature spermatids. An optimal testicular RA concentration is maintained by retinaldehyde dehydrogenases (ALDHs), which oxidize RA precursors to produce RA, whereas the CYP26 class of enzymes catabolizes (oxidize) RA into inactive metabolites. The objective was to elucidate gene expression of these RA‐metabolizing enzymes (ALDH1A1, ALDH1A2, ALDH1A3, CYP26A1, CYP26B1 and CYP26C1) and their protein presence in testes of young, peripubertal and adult dogs. Genes encoding RA‐synthesizing isozymes ALDH1A1, ALDH1A2 and ALDH1A3 and RA‐catabolizing isomers CYP26A1, CYP26B1 and CYP26C1 were expressed in testis at varying levels during testicular development from birth to adulthood in dogs. Based on detailed analyses of mRNA expression patterns, ALDH1A2 was regarded as a primary RA‐synthesizing enzyme and CYP26B1 as a critical RA‐hydrolysing enzyme; presumably, these genes have vital roles in maintaining RA homeostasis, which is imperative to spermatogenesis and other testicular functions in post‐natal canine testis.  相似文献   

9.
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本研究旨在观察羊驼睾丸的出生后发育和精子发生过程中的细胞凋亡及凋亡相关蛋白Bcl2和Caspase3 的定位.取材新生、12月龄和24月龄羊驼的睾丸,用TUNEL法检测睾丸发育和精子发生过程的细胞凋亡,用免疫组织化学技术检测凋亡相关蛋白Bcl2和Caspase3在羊驼出生后发育和精子发生过程中的定位.结果显示在新生羊驼睾丸未检测到TUNEL阳性细胞,Caspase3和Bcl2表达于间质细胞,提示在新生期凋亡蛋白参与间质细胞凋亡的调节,为曲精小管的发育提供空间;12月龄羊驼睾丸TUNEL阳性细胞定位于曲精小管中央部分,Caspase3 和Bcl2定位于间质细胞和曲精小管中央生殖细胞,提示在青春期(12月龄)羊驼睾丸,细胞凋亡和凋亡相关蛋白参与曲精小管管腔形成的调节;24月龄羊驼睾丸TUNEL阳性细胞定位于精原细胞、精母细胞和精子细胞,Caspase3 和Bcl2定位于间质细胞和各个发育阶段的生精细胞,Caspase3阳性细胞在精原细胞最高,向精母细胞和精子细胞逐渐减少,Bcl2在精原细胞弱阳性表达,在血睾屏障以内的曲精小管近腔室部分呈弥散性强阳性表达,提示在性成熟(24月龄)羊驼睾丸精子发生过程中,细胞凋亡主要发生于精原细胞和早期精母细胞,Bcl2可能抑制精母细胞之后生殖细胞的凋亡.结果提示在羊驼睾丸出生后发育和精子发生过程中存在细胞凋亡现象;凋亡蛋白Caspase3和Bcl2参与羊驼睾丸发育和精子发生过程中细胞凋亡的调节.  相似文献   

11.
The transition from male primitive germ cells (gonocytes) to type A spermatogonia in the neonatal testis is the initial process and a crucial process in spermatogenesis. However, in large domestic animals, the physiological and biochemical characteristics of germ cells during the developmental processes remain largely unknown. In this study, we characterized bovine germ cells in the developing testis from the neonatal stage to the adult stage. The binding of the lectin Dolichos biflorus agglutinin (DBA) and the expression of ubiquitin carboxyl-terminal hydrolase 1 (UCHL1) were restricted to gonocytes in the neonatal testis and spermatogonia in the adult testis. Gonocytes also expressed a germ cell marker (VASA) and stem cell markers (NANOG and OCT3/4), while the expressions of these markers in the adult testis were restricted to differentiated spermatic cells and were rarely expressed in spermatogonia. We subsequently utilized these markers to characterize gonocytes and spermatogonia after culture in vitro. Spermatogonia that were collected from the adult testis formed colonies in vitro only for one week. On the other hand, gonocytes from the neonatal testis could proliferate and form colonies after every passage for 1.5 months in culture. These colonies retained undifferentiated states of gonocytes as confirmed by the expression of both germ cell and stem cell markers. Moreover, a transplantation assay using immunodeficient mice testes showed that long-term cultured cells derived from gonocytes were able to colonize in the recipient testis. These results indicated that bovine gonocytes could maintain germ cell and stem cell potential in vitro.  相似文献   

12.
13.
The expression of cyclins A, D1, D2 and E were examined immunohistochemically in 5 canine normal testes and 31 testicular tumors, including 14 seminomas, 11 Sertoli cell tumors and 6 Leydig cell tumors. In canine normal testes, cyclin A expression was detected in spermatogonia and primary spermatocytes. This suggests that A-type cyclins may play some role in canine spermatogenesis. Cyclin A expression was also observed in 13/14 (92.9%) seminomas and 2/11 (18.2%) Sertoli cell tumors, but no positive reaction was observed in Leydig cell tumors. Parallel examinations for cyclins D1, D2 and E gave negative results in canine normal testes and testicular tumors. High levels of cyclin A expression in canine seminomas indicate that the neoplastic germ cells may be arrested at the spermatogonia and primary spermatocyte stages of differentiation.  相似文献   

14.
Aging is a major risk factor for spermatogenesis deterioration. However, the influence of age on spermatogenic stem cells and their progenitors in bulls is largely unknown. Here, we report age-related changes in undifferentiated and differentiating spermatogonia in Japanese Black cattle with nearly constant sperm output, by using spermatogonial markers. The numbers of differentiating spermatogonia and more differentiated spermatogenic cells were significantly decreased in aged bovine testes compared with those in young testes. In contrast, the number of undifferentiated spermatogonia was maintained, and their proliferative activity did not differ significantly between young and aged bovine testes. Although severe calcification was only observed to a small extent in aged testes, fewer Sertoli cells and interstitial fibrosis were observed in noncalcified testicular regions. These results suggest that, even in old bulls with nearly constant sperm output, testicular spermatogenic activity declined whereas undifferentiated spermatogonia numbers were maintained. Thus, we propose that undifferentiated spermatogonia may be resistant to age-related changes in bovine testes. Because undifferentiated spermatogonia may contain stem cell activity, our findings highlight the potential utility of undifferentiated spermatogonia as an agricultural resource to produce spermatozoa beyond the natural bovine lifetime through transplantation and in vitro spermatogenesis in future animal production.  相似文献   

15.
Connexin43 (Cx43) is a major protein of myometrial gap junctions. The number of Cx43 gap junctions increase dramatically with the onset of labour in association with development of synchronized uterine contractions. The formation of myometrial gap junctions follows an increase in the oestrogen to progesterone ratio indicating an important role of steroid hormones in regulating Cx43 expression at term. However, no relationship has been established between the expression of Cx43 in the non‐pregnant myometrium and concentration of steroid hormones during the oestrous cycle. Here, we used immunofluorescence and Western blotting to analyse the expression of Cx43 gap junctions in the myometrium of pre‐pubertal pigs (n = 7) and mature pigs at pre‐ovulatory (n = 7), luteal (n = 5) and late luteal (n = 3) stages of the oestrous cycle. The number of Cx43 gap junctions calculated per 1 mm2 of the myometrial section was low in pre‐pubertal pigs and significantly higher (p < 0.022) in pre‐ovulatory animals. In relation to pre‐ovulatory animals the number of myometrial gap junctions was significantly lower (p < 0.019) at the luteal phase and correlated with significantly higher (p < 0.005) concentration of endogenous progesterone. Phosphorylated isoforms of Cx43 protein were expressed in the myometrium of pre‐pubertal pigs and mature animals at pre‐ovulatory and late luteal phases, while they were down regulated at the luteal stage. These results indicate that changes of Cx43 expression in the porcine myometrium during the oestrous cycle may be regulated by progesterone concentration and may contribute to the modulation of uterine motility.  相似文献   

16.
对牦牛和牦牛与黄牛杂交1-3代牛的睾丸进行了比较组织学的研究,结果表明:F1代牛睾丸中可见少量的初级精母细胞,F2代牛睾丸中可见少量的次级精母细胞和精子细胞,F3代牛睾丸中具备各级生精细胞和精子。  相似文献   

17.
The aims of the present study were to clarify the effect of kisspeptin‐10 (Kp10) on the secretion of luteinizing hormone (LH) and testosterone (T) in pre‐pubertal and post‐pubertal male ruminants. Four male goats (Shiba goats) were given an intravenous (i.v.) injection of Kp10 (5 µg/kg body weight (b.w.)), gonadotoropin‐releasing hormone (GnRH, 1 µg/kg b.w.), or 2 mL of saline as a control at the ages of 3 (pre‐pubertal) and 6 (post‐pubertal) months. A single i.v. injection of Kp10 significantly stimulated the release of LH and T in both groups. The area under the response curve (AUC) of LH for a 60‐min period after the i.v. injection of Kp10 was significantly greater in the pre‐pubertal goats (P < 0.05). The AUC of T for a 120 min period post‐injection did not differ between the two age groups. A single i.v. injection of GnRH also significantly stimulated the release of LH and T in both groups (P < 0.05). The secretory pattern of LH and T in response to GnRH resembled that in response to Kp10. These results show that the LH‐releasing response to Kp10 is greater in pre‐pubertal than post‐pubertal male goats. They also show that Kp10, as well as GnRH, is able to stimulate the release of T in male goats.  相似文献   

18.
19.
The anatomy and histology of the male genital tract of the lesser anteater were studied. Fine details of spermatozoa regarding their genesis and morphology were also studied in six adult specimens. The testes lie in the pelvic cavity. The deferent duct emerges from the epididymis and opens into the ejaculatory duct, which drains into the membranous urethra. Accessory glands (prostate, seminal vesicle and bulbourethral gland) are histologically similar to those described in other mammals. The short penis presents an urethral orifice, while the corpus spongiosum becomes thinner at the end indicating the absence of a histologically defined glans. The seminiferous epithelium shows: (1) Sertoli cells with deep nuclear indentations, (2) spermatogonia with crusty‐like chromatin, (3) spermatocytes at different stages of maturation and (4) three morphologically distinct stages of spermatid differentiation according to nuclear shape, acrosome development and chromatin condensation. Sperm heads appear oval. The length of the spermatozoa averages 67.33 ± 1.60 μm. Two specimens with inactive spermatogenesis were azoospermic. Their testes and epididymis presented sizes smaller than those with active spermatogenesis. These studies together with others in anteaters may contribute to successful breeding in conservation programmes.  相似文献   

20.
It has been suggested that insulin-like growth factor-I (IGF-I) plays an important role in the regulation of spermatogenesis in the testes. Its signal is mediated predominantly by the IGF-I receptor (IGF-IR). Signalling through IGF-IR has been shown to have a potent survival function. IGF-IR, a transmembrane tyrosine kinase, is widely expressed across many cell types. In this study, we demonstrated the distribution of IGF-IR in testes of differently aged rats. Anti-IGF-IR is a rabbit polyclonal antibody raised against a peptide mapping at the carboxy terminus of the IGF-IR of human origin. Testicular specimens were fixed in Bouin's solution and embedded in paraffin. The paraffin-embedded sections were processed for standard immunohistochemistry by the labelled streptavidin-biotin technique. At postnatal day 19, IGF-IR immunoreactivity was seen moderately in spermatogonia, and slightly both in leptotene and zygotene primary spermatocytes. At postnatal day 35, immunoreactivity was seen slightly both in the pachytene primary spermatocytes and Leydig cells. Although there was intense immunoreactivity in the Leydig cells and in the elongated spermatids on days 50 and 70, the intensity of reaction was decreased in the elongated spermatids in the 10th month. Our results suggest that IGF-IR may play significant roles in testicular function and germ cell development.  相似文献   

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