共查询到20条相似文献，搜索用时 15 毫秒
1.
W Van den Broeck M D'haeseleer M Coryn P Simoens 《Reproduction in domestic animals》2002,37(5):314-320
This study describes the localization of progesterone receptors (PR) in the bovine ovary. Ovaries were obtained from 11 non‐pregnant and two pregnant cows. Progesterone receptors were visualized by immunohistochemistry on paraffin sections. Nuclear staining for PR was observed in cells of the follicles, corpora lutea, theca layers, surface epithelium, tunica albuginea, and in superficial and deep stroma cells. No staining was noticed in apoptotic bodies of atretic follicles. Expression of PR in follicle cells indicates an intrafollicular role of progesterone. The higher expression in thecal cells compared with follicle cells indicates that thecal cells mediate some effects of progesterone on the follicular development. Superficial stroma cells showing high expression might have a similar influence on primordial and primary follicles. In general, luteal cells had a lower expression than follicle cells, which may be explained by the down‐regulatory effect of locally produced progesterone. The lower expression in luteal cells during pregnancy can be due to the longer life span of this corpus luteum and concomitant degeneration of its PR. The high and rather constant expression of PR in cells of the surface epithelium remains to be elucidated. 相似文献
2.
W Van den Broeck M D'haeseleer M Coryn P Simoens 《Reproduction in domestic animals》2002,37(3):164-170
This study describes the localization of progesterone receptors (PR) in the bovine ovary. Ovaries were obtained from 11 non‐pregnant and two pregnant cows. Progesterone receptors were visualized by immunohistochemistry on paraffin sections. Nuclear staining for PR was observed in cells of the follicles, corpora lutea, theca layers, surface epithelium, tunica albuginea, and in superficial and deep stroma cells. No staining was noticed in apoptotic bodies of atretic follicles. Expression of PR in follicle cells indicates an intrafollicular role of progesterone. The higher expression in thecal cells compared with follicle cells indicates that thecal cells mediate some effects of progesterone on the follicular development. Superficial stroma cells showing high expression might have a similar influence on primordial and primary follicles. In general, luteal cells had a lower expression than follicle cells, which may be explained by the down‐regulatory effect of locally produced progesterone. The lower expression in luteal cells during pregnancy can be due to the longer life span of this corpus luteum and concomitant degeneration of its PR. The high and rather constant expression of PR in cells of the surface epithelium remains to be elucidated. 相似文献
3.
D'Haeseleer M Cornillie P Simoens P van den Broeck W 《Anatomia, histologia, embryologia》2006,35(5):334-342
In the present study oestrogen receptor alpha(ERalpha) and oestrogen receptor beta (ERbeta) mRNA were localized in various ovarian cell types of 23 cows at different stages of the oestrous cycle. ERalpha was detected by immunohistochemistry and the localization of ERbeta mRNA was examined using in situ hybridization. The immunostaining of ERalpha was low in the ovarian follicles, tunica albuginea and surface epithelium, but high in cells of the deep stroma and superficial stroma, which indicates a functional role of ERalpha in the cells surrounding the follicles. In contrast, ERbeta mRNA scores were low to moderate in primordial and primary follicles, and increased with the development of the follicle. ERbeta mRNA scores were higher in cystic follicles than in obliterative follicles. In the corpora lutea and corpora albicantia the scores for ERbeta mRNA were moderate. Furthermore, in the corpora lutea, ERbeta mRNA levels showed cyclic variations and were low during early dioestrus. The correlation between plasma progesterone levels and the score for ER was low and negative in all ovarian cell types. This study demonstrates the predominant role of ERbeta over ERalpha in bovine ovarian structures. Furthermore, the colocalization of both ERbeta mRNA and ERalpha in most cell types suggests possible interactions between both ER subtypes. 相似文献
4.
M. M. D&#x;Haeseleer W. L. M. Van den Broeck P. Simoens 《Anatomia, histologia, embryologia》2005,34(Z1):14-14
The oestrogen receptor beta (ERß) is largely distributed in the ovary of many species but data for the bovine ovary are scare. Therefore, the expression of ERß mRNA in the different follicles of the bovine ovary was studied using in situ hybridization. Ovarian tissue sections of three cows with different plasma progesterone concentrations were used (cow 1: 3.50 ng/ml; cow 2: 1.00 ng/ml, cow 3: 0.35 ng/ml). A 602 bp fragment of ERß mRNA was cloned, sequenced and digoxigenin (DIG)‐labelled. Subsequently, in situ hybridization was performed by incubating the sections with the DIG‐labelled RNA anti‐sense probe. For the semi‐quantitative evaluation of ERß mRNA expression the ERß mRNA score (SER) was determined for the different follicular cell types using the formula: SER = 0.n0 + 1.n1+ 2.n2 + 3.n3 with n0, n1, n2, n3 indicating the percentage of cells exhibiting a staining intensity 0 (absent), 1 (weak), 2 (moderate) or 3 (strong), respectively. High ER mRNA levels were noticed in primordial and primary follicle cells, and suggest a role of ER mRNA in early folliculogenesis. A lower SER was observed in the granulosa cells of secondary and tertiary follicles. This significant difference in the SER of follicle cells during follicular growth may be associated with cell proliferation. In obliterative and cystic atretic follicles high SER were observed, although ERß mRNA levels in obliterative follicles showed much inter‐individual variation. This is suggestive for ERß mediated oestrogen action in atretic follicles. In the corpora lutea moderate ERß mRNA levels were noticed. Our findings are in accordance with studies in the ewe in which corpora lutea cells synthesize estrogen. These preliminary findings will be further elaborated in a higher number of cows to examine the role of ERß in the ovary throughout the oestrus cycle. 相似文献
5.
The localization of oestrogen receptor beta (ESR2) mRNA, in this article denominated as (ERbeta) mRNA, was examined using in situ hybridization in the ovaries of randomly selected cows, irrespective of the cycle stage of the animals. A 602-bp fragment of ERbeta mRNA was cloned, sequenced and digoxigenin (DIG)-labelled. Semi-quantitative evaluation showed that the scores for ERbeta mRNA were moderate to high in the follicle cells of both primordial and primary follicles, but lower in granulosa cells of secondary follicles. In vital tertiary follicles, the total ERbeta mRNA expression was low but varied between the different animals. In both obliterative and cystic atretic follicles, high to moderate ERbeta mRNA scores were noticed in the granulosa cells. The stroma cells surrounding primordial and primary follicles and the theca cells of secondary follicles showed moderate ERbeta mRNA levels, whereas the ERbeta mRNA score in theca interna and theca externa cells of vital tertiary follicles was distinctly higher. In the theca cells of atretic follicles the score was even higher. Cells of corpora hemorrhagica and corpora lutea had moderate ERbeta mRNA scores, while higher scores were seen in cells of corpora albicantia. Cells of the surface epithelium had a moderate score for ERbeta mRNA, whereas cells of the tunica albuginea and deep stroma showed high ERbeta mRNA scores. The present findings have clearly established a cell-specific localization of ERbeta mRNA in several cell types in the bovine ovary. 相似文献
6.
The oestrogen receptor beta (ERß) is largely distributed in the ovary of many species but data for the bovine ovary are scare. Therefore, the expression of ERß mRNA in the different follicles of the bovine ovary was studied using in situ hybridization. Ovarian tissue sections of three cows with different plasma progesterone concentrations were used (cow 1: 3.50 ng/ml; cow 2: 1.00 ng/ml, cow 3: 0.35 ng/ml). A 602 bp fragment of ERß mRNA was cloned, sequenced and digoxigenin (DIG)-labelled. Subsequently, in situ hybridization was performed by incubating the sections with the DIG-labelled RNA anti-sense probe. For the semi-quantitative evaluation of ERß mRNA expression the ERß mRNA score (SER) was determined for the different follicular cell types using the formula: SER = 0.n0 + 1.n1+ 2.n2 + 3.n3 with n0, n1, n2, n3 indicating the percentage of cells exhibiting a staining intensity 0 (absent), 1 (weak), 2 (moderate) or 3 (strong), respectively. High ER mRNA levels were noticed in primordial and primary follicle cells, and suggest a role of ER mRNA in early folliculogenesis. A lower SER was observed in the granulosa cells of secondary and tertiary follicles. This significant difference in the SER of follicle cells during follicular growth may be associated with cell proliferation. In obliterative and cystic atretic follicles high SER were observed, although ERß mRNA levels in obliterative follicles showed much inter-individual variation. This is suggestive for ERß mediated oestrogen action in atretic follicles. In the corpora lutea moderate ERß mRNA levels were noticed. Our findings are in accordance with studies in the ewe in which corpora lutea cells synthesize estrogen. These preliminary findings will be further elaborated in a higher number of cows to examine the role of ERß in the ovary throughout the oestrus cycle. 相似文献
7.
Dynamics of ovarian follicular development in cattle following hysterectomy and during early pregnancy 总被引：2，自引：0，他引：2
Three experiments were conducted to evaluate ovarian follicular dynamics and functional activity during pregnancy in cattle. In 11 pregnant Charolais cows of Experiment I, size of largest follicle, number of follicles and accumulated follicle size were reduced by day 27 of pregnancy on the ovary bearing the corpus luteum (CL) but not on the non-CL bearing ovary. In experiment II, local attenuation of ovarian follicular development on the CL bearing ovary of seven pregnant heifers was evident compared to the contralateral ovary without the CL. However, in four hysterectomized heifers, follicular development was sustained on both the CL- and non-CL bearing ovaries when CL maintenance was achieved without presence of the uterus or conceptus. In Experiment III, steroidogenic characteristics of the largest and second largest follicles at 17 d postestrus were evaluated for seven pregnant and six cyclic cattle. Follicle by physiological status interactions were detected for both aromatase activity of the follicle and follicular fluid concentrations of estradiol and progesterone. In cyclic cows, the largest follicle had appreciably more aromatase activity than did the second largest follicle; whereas, aromatase activity of the largest follicle from pregnant cows was less than that of cyclic cows. However, in pregnant cows the second largest follicle became the estrogen-active follicle, and this follicle occurred with a higher frequency on the ovary contralateral to the CL-bearing ovary. These changes in aromatase activity were reflected by parallel changes in estrogen concentrations of follicular fluid. The higher progesterone concentration in follicular fluid of the largest follicle in pregnant cows provided further confirmation of their atretic status. In conclusion, during early pregnancy the conceptus and/or uterus ipsilateral to the conceptus appear to secrete compounds which alter local follicular steroidogenic activity and attenuate subsequent follicular growth between 17 to 34 d of pregnancy on the CL-bearing ovary. This local mechanism acting within the ovary may contribute to the antiluteolytic effects of early pregnancy in cattle. 相似文献
8.
运用组织学常规石蜡切片-HE染色和过碘酸-雪夫染色（PAs）方法,分别对3日龄及165日龄育成猪卵巢组织结构、各级卵泡的发育变化特点及其黏多糖分布情况进行了研究。结果显示,3日龄的猪卵巢皮质、髓质界限模糊,皮质部分由外向内依次分布着密集的卵原细胞和卵原细胞巢、共质体样的卵原细胞群,皮质深层与髓质相邻处分布着合胞体样的卵母细胞簇状结构和卵泡。育成猪卵巢中,皮、髓质界限明显,能观察到原始卵泡、初级卵泡、次级卵泡及近成熟卵泡,但是很少能见到黄体的结构。PAS染色结果表明,3日龄的猪卵巢中PAS阳性反应主要分布于卵原细胞周围的基质、卵原细胞巢和合胞体的外膜上,以及原始卵泡周围的基质、初级卵泡的卵泡膜及刚形成的透明带上,此外卵巢的白膜、髓质的结缔组织、血管壁及卵巢网周围也可见到广泛的阳性着色。育成猪卵巢中,PAS阳性反应主要分布于基质、生长卵泡的卵泡膜、卵泡的透明带、次级卵泡的卵泡液、黄体被膜及髓质的结缔组织和血管壁。 相似文献
9.
Lysophosphatidic acid expression in theca cells depends on the type of bovine ovarian follicle 
下载免费PDF全文
下载免费PDF全文 E Sinderewicz K Grycmacher D Boruszewska I Kowalczyk‐Zięba I Woclawek‐Potocka 《Reproduction in domestic animals》2017,52(1):28-34
Lysophosphatidic acid (LPA) exerts various actions on the mammalian reproductive system. In cows, LPA stimulates the synthesis and secretion of luteotropic factors in the ovary, which affects the growth and development of ovarian follicles. The role of LPA in granulosa cells, oocyte and oocyte‐cumulus complex (COC) has previously been investigated; but its role in the theca layer, which is an important structural and functional component of the ovarian follicle, is still unclear. The goal of this study was to investigate the expression of LPA in theca cells originating from different bovine ovarian follicle types. Theca cells were separated from healthy, transitional and atretic ovarian follicles, based on intrafollicular estradiol: progesterone ratios. LPA concentration in the follicular fluid (FF) in different follicle types was measured, and expression of the enzymes responsible for LPA synthesis (autotaxin [AX], phospholipase A2 [PLA2]) and receptors for LPA (LPAR1‐4) were determined. The obtained results confirmed the follicle‐type dependent presence of LPA in the FF of the bovine ovarian follicles. The highest concentration of LPA was detected in follicles classified as healthy and dominant. LPAR1‐4, PLA2 and AX expression in theca cells in all of the types of follicles examined were detected at mRNA and protein level. These results suggest that theca cells can be a source of LPA synthesis other than granulosa cells and COCs, as well as the target for its action in the bovine ovarian follicle, with PLA2 and LPAR4 playing major roles in LPA synthesis and action. 相似文献
10.
Apart from estrone-3-sulfate (E1S) the bovine placenta produces progesterone (P4), though the corpus luteum is the major source of P4 responsible for maintaining pregnancy. So far the biological function of placental steroids in cattle is largely unknown. However, since the local availability of free estrone (E1) in the placenta seems to be controlled by sulfatase and sulfotranferase, the hypothesis was developed that placental estrogens and P4 might act as local regulatory factors. To test for such a function placentomes from 150, 220, 240, 270 days (D) pregnant and parturient cows were screened immunohistochemically for progesterone and estrogen receptors (PR, ER). PR were found at all stages in the caruncle in stromal cells and capillary pericytes but only at parturition in arterial walls. Percentage of PR-positive caruncular stromal cells (CSC) increased (P<0.05) from 51.8+/-2.6% at D150 to 58.9+/-1.8% at parturition. ER were detected in CSC, caruncular epithelial (CE) cells and in caruncular capillary pericytes. Mean percentage of ER-positive CSC decreased from 39.0+/-5.9% in pregnant cows to 17.5+/-8.3% at parturition (P<0.05). In CE all cells exhibited positive signals with the exception of those immediately surrounding large primary chorionic villi. Proliferation was assessed immunohistochemically by determining the percentage of Ki67-antigen positive cells. Highest values (P<0.001) were obtained for CE (58.0-68.3%), followed by the trophoblast (23.3-25.4%), CSC (10.6-45.3%) and the stroma of the chorionic villi (2.9-10.5%). A transient depression of proliferation in CSC between D150-270 (P<0.05) paralleled local estrogen tissue concentrations. The results suggest that placental estrogens and P4 are important factors controlling caruncular growth, differentiation and function. 相似文献
11.
Production of mitogenic factors by cell types of bovine large estrogen-active and estrogen-inactive follicles 总被引：3，自引：0，他引：3
This study investigated whether large follicles (estrogen-active and estrogen-inactive) of cows produce factors with mitogenic activity. Large, preovulatory follicles (greater than or equal to 9 mm in diameter) were classified as estrogen-active or -inactive based on ratio of estrogen: progesterone concentrations in follicular fluid. After incubation of granulosa cells and thecal tissues from follicles, granulosa cell conditioned media (GCM), thecal conditioned media (TCM) and follicular fluid (FFL) were evaluated for effects on proliferation of bovine aortic endothelial (BAE) and BALB/3T3 (3T3) cells. Pools of GCM, TCM and FFL stimulated proliferation of BAE and 3T3 in a dose-dependent fashion. Across all follicles (n = 20), GCM had greater stimulatory effect on proliferation of BAE than on proliferation of 3T3 (135 vs 115% of unconditioned media controls), whereas TCM stimulated proliferation of BAE and 3T3 to a similar extent (128 and 128%). Across type (GCM and TCM) of conditioned media, estrogen-active follicles stimulated proliferation of BAE more than proliferation of 3T3 (137 vs 121% of unconditioned media controls), whereas estrogen-inactive follicles stimulated proliferation of BAE and 3T3 to a similar extent (120 vs 122%). As observed for GCM, FFL across all follicles had a greater stimulatory effect on proliferation of BAE than on proliferation of 3T3 (159 vs 141%). Granulosa-conditioned media stimulated proliferation of BAE and 3T3 only when obtained from estrogen-active follicles; mitogenic activities of TCM and FFL were not influenced by type of follicle. These data demonstrate that granulosa cells of large preovulatory bovine follicles secrete a mitogenic factor(s) that is more stimulatory for proliferation of BAE than for 3T3.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
12.
Koji IIJIMA Yukiko TAWARA Takashi SHIMIZU Keiichiro YOGO Hiroshi SASADA Eimei SATO 《Animal Science Journal》2006,77(6):574-581
Vascular endothelial growth factor (VEGF) is an important angiogenic factor in the ovary, but the localization of VEGF in the ovary of neonatal animals is poorly understood. A clear understanding of the relationship between the formation of the thecal layer and the cell‐specific expression of the VEGF system during follicular development in the neonatal ovary is still lacking. Immature female Wistar‐Imamichi rats used in this study were killed by decapitation 5, 7, 9 and 11 days after birth, and their ovaries were removed and subjected to histological and immunohistochemical observation. The number of primordial follicles had decreased in the ovaries at day 11 compared with that at day 5. The number of secondary follicles significantly increased with age. In the morphological observation of secondary follicles, we found that the theca layer (70 µm in diameter of follicles) began to form at day 9 and was completely formed at day 11. An endothelial cell marker, CD31, VEGF and Flk‐1 were located in the stromal tissues in the ovaries on each day examined after birth. In particular, in the ovaries at day 9 and day 11, when the secondary follicles appeared, CD31, VEGF and Flk‐1 were expressed in the theca layer. Flt‐1 was expressed in the oocytes of the ovaries at day 5 and day 7, and the sites of its expression changed to stromal and thecal tissues at day 9 and day 11. In conclusion, we provide the first evidence that the theca layer of secondary follicles begin to form at day 9 after birth and that VEGF and Flk‐1 may be able to stimulate the differentiation of stromal‐interstitial cells into thecal cells and the formation of the thecal vasculature in the neonatal rat ovaries, suggesting that the VEGF system may be involved in the formation of the thecal layer and vasculature during folliculogenesis in the neonatal rat. 相似文献
13.
A peptidyl-prolyl isomerase, Pin 1, has been shown to play a role in the regulation of cell cycle progression, both in vitro and in vivo. However, the involvement of Pin 1 during follicular development is not well understood. The aim of this study was first to investigate the expression of Pin 1 mRNA in the granulosa and theca cells of the follicle at different developmental stages of follicles in the bovine ovary, and second, to examine the effects of follicle-stimulating hormone (FSH) and estradiol (E2) on the expression of Pin 1 in the cultured bovine granulosa cells. Follicles were classified into four groups based on the diameter (dominant follicles >8.5mm in diameter, subordinate follicles <8.5mm in diameter) and the relative levels of E2 and progesterone (P4) (E2:P4>1, estrogen active; E2:P4<1, estrogen inactive): i.e. preovulatory dominant follicles (POFs); E2 active dominant follicles (EADs); E2 inactive dominant follicles (EIDs); small follicles (SFs). The expression of the Pin 1 gene was significantly increased in the granulosa cells of EADs as compared with those of other follicles, whereas its expression in theca cells did not differ among follicles at different developmental stages. The concentration of 5 ng/ml FSH alone and the combination of 1 ng/ml E2 and 5 ng/ml FSH stimulated the expression of the Pin 1 gene in bovine granulosa cells. Our data provide the first evidence that Pin 1 expression in the granulosa cells but not the theca cells changes during follicular development, and that FSH stimulate the expression of the Pin 1 gene. These results suggest that Pin 1 regulates the timing of cell proliferation and may act as an intracellular signal responder in the granulosa cells during bovine follicle development. 相似文献
14.
15.
Tetsuka M Asada M Mogoe T Fukui Y Ishikawa H Ohsumi S 《The Journal of reproduction and development》2004,50(4):381-389
This study describes the morphological and morphometrical changes associated with prepubertal ovarian development in the Antarctic minke whale (Balaenoptera bonaerensis). Ovaries were harvested from 94 immature minke whales caught in the Antarctic Ocean during the summer feeding season (December-March). Notable differences in ovarian size and morphology were found among animals. Up to 10 folds difference in ovarian weight was found among prepubertal whales of similar body size. During the prepubertal period, ovaries grew slowly and approximately doubled their weight. The morphologies of right and left ovaries were almost identical while the growth of the ovary appears to occur preferentially on the right side. The most striking morphological feature was numerous small antral follicles less than 5 mm in diameter found in ovaries of younger immature whales. The occurrence of these ovaries was highest in whales less than 6 m long and gradually decreased as body length increased. In larger whales, the occurrence of ovaries with a smaller number of follicles up to 10 mm and thick tunica albuginea increased. Thus, the ovary of the Antarctic minke whale experiences bursts of small follicular development during the early prepubertal period before becoming a more developed ovary with fewer but larger follicles, and thick tunica albuginea. 相似文献
16.
Hongwei Duan Longfei Xiao Junjie Hu Yong Zhang Xingxu Zhao Wenbo Ge Yuting Jiang Liangli Song Shanshan Yang Wenze Luo 《Reproduction in domestic animals》2019,54(10):1305-1312
Oestrogen, androgen and progesterone are involved in the regulation of uterine physiological functions, with the participation of the following proteins: oestrogen receptor (ER), androgen receptor (AR) and progesterone nuclear receptor (PGR). In this study, we used immunohistochemistry to detect the localization of ERα, ERβ, AR and PGR in sheep uterus. Additionally, we used real‐time polymerase chain reaction (RT‐qPCR) and Western blot technique to analyse their expression profiles at different stages of sheep oestrous cycle in the endometrium and myometrium. Immunohistochemical analysis showed that ERα, ERβ, AR and PGR were present in sheep uterus in oestrus, mainly in the uterine luminal epithelium, stroma, gland and myometrium. Real‐time polymerase chain reaction results showed that in the endometrium, ERα expression level was highest in oestrus. ERβ and PGR, instead, were highly expressed in pro‐oestrus. In the myometrium, ERα was highly expressed in both oestrus and pro‐oestrus, and ERβ was highly expressed in oestrus and dioestrus. Progesterone nuclear receptor expression was highest in oestrus, followed by metoestrus. In the endometrium, both receptors ERα and ERβ were abundant in pro‐oestrus, while the maximum AR protein content was found in oestrus. At this stage of the oestrous cycle, PGR protein concentration in the myometrium was significantly lower than those observed in other stages. These results suggest that these receptors are important for sheep reproductive function, as their expression at mRNA and protein levels exhibits particular time‐ and tissue‐specific profiles along the oestrous cycle. 相似文献
17.
Salvetti NR Acosta JC Gimeno EJ Müller LA Mazzini RA Taboada AF Ortega HH 《Veterinary pathology》2007,44(3):373-378
The purpose of this study was to determine by immunohistochemistry the expression of estrogen and progesterone receptors in ovarian follicular structures from cows with cystic ovarian disease (COD) and to compare these with normal ovarian structures. Secondary, tertiary, atretic, and cystic follicles were evaluated. The follicular cysts of animals with COD presented a significantly higher expression of estrogen receptor alpha in all follicular layers than secondary, tertiary, and atretic follicles in both groups (P < .05). The intensity of estrogen receptor beta in the granulosa cell layer was stronger in tertiary than in secondary and atretic follicles in normal animals (P < .05) and in growing and cystic follicles in animals with COD (P < .05). Theca cells were scarcely stained in the 2 groups. Growing follicles and cysts from COD animals were less stained than tertiary follicles from normal animals (P < .05). Differences did not exist between the 2 groups with regard to the progesterone receptor. Ovaries of animals with COD exhibited altered estrogen receptors expression compared with that in normal animals. 相似文献
18.
双峰驼卵巢的组织结构 总被引：5，自引：1，他引：5
应用组织学方法对双峰驼卵巢的形态结构进行了显微与亚显微观察。结果显示 ,双峰驼卵巢表面被覆单层立方至单层扁平的生殖上皮 ,无排卵窝 ,上皮下为致密结缔组织白膜 ,卵巢实质由外周的皮质和中央的髓质构成。皮质中原始卵泡和初级卵胞数量稀少 ,其分布位置更靠近皮质中层 ,偶见同一卵泡内含 2个卵母细胞。体积大小和发育阶段不同的次级卵泡与三级卵泡闭锁时 ,所发生的形态变化不一致 ,可出现实心和囊状 2种闭锁卵泡。黄体中以粒性黄体细胞占优势 ,其细胞质中含大量脂质泡而呈海绵样。卵巢髓质中除含大量血管外 ,还见卵巢网分布 相似文献
19.
Spicer LJ Alvarez P Prado TM Morgan GL Hamilton TD 《Domestic animal endocrinology》2000,18(2):265-278
The objective of this study was to determine if increased secretion of intraovarian insulin-like growth factor-I (IGF-I), experimentally induced via minipumps, affects follicular function in cattle. Fourteen cycling Holstein cows were divided equally into two groups: Control, osmotic minipumps (containing vehicle) surgically inserted into each ovary, or IGF-I treated, osmotic minipumps as in Controls but pumping 2.0 microg of recombinant human IGF-I per hr for 7 days. All cows were synchronized with prostaglandin F(2alpha) 0.10) between Control and IGF-I-treated cows during Days 2 to 6 of treatment. IGF-I treatment increased (P<0.05) estradiol concentrations in follicular fluid of small follicles, but had no effect (P<0.10) on estradiol concentrations in follicular fluid of large follicles, or on progesterone, androstenedione, or IGF binding protein concentrations in small or large follicles. We conclude that a 7-day infusion of IGF-I directly into the stroma of the ovary altered follicular growth and follicular fluid estradiol concentrations. 相似文献
20.
Hampton JH Manikkam M Lubahn DB Smith MF Garverick HA 《Domestic animal endocrinology》2004,27(1):81-88
Previous studies have shown that androgen receptor (AR) is expressed in granulosa cells of healthy, growing ovarian follicles in rats and primates. However, AR expression in the bovine ovary has not been examined. Therefore, a 346-base pair segment of the bovine AR was cloned and sequenced. Using a ribonuclease protection assay, AR expression was detected in total RNA from bovine ovarian cortex. Expression (absence or presence) of AR mRNA was detected by in situ hybridization in bovine ovarian cortex. Follicles (n = 32) were classified as follows: type 1 (1 layer of flattened granulosa cells), type 2 (1-1.5 layers of cuboidal granulosa cells), type 3 (2-3 layers of granulosa cells), type 4 (4-6 layers of cuboidal granulosa cells and formation of thecal layer), and type 5 (>6 layers of cuboidal granulosa cells, defined theca layer, and antrum formation). Frequency of AR mRNA expression increased (P < 0.001) as follicles entered the growing pool. Expression of AR mRNA was absent in type 1 follicles (n = 8), but present in the granulosa cells of 41% of type 2 follicles (n = 12). In types 3-5 follicles, AR mRNA expression was present in granulosa cells of 100% of follicles examined (n = 4, 4, and 4, respectively) and was greater than type 1 follicles (P = 0.002). These data provide evidence of AR mRNA expression in bovine follicles and suggest that AR mRNA increases during early follicle development. 相似文献