• Development and Reproduction
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• v.4 no.1
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• pp.13-17
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• 2000

Follicle stimulating hormone (FSH) stimulates follicle growth, and inhibits the follicle atresia in the immature rodent ovaries. The present study was carried out to know the histological changes of ovarian follicles after FSH treatment in the prepubertal mice. Ten i.u. of recombinant FSH was i.p. injected on 3 weeks old mice. After the treatment, at 1, 2 and 3 days, left ovaries were collected for the histological study. The atretic ratio of preantral follicles increased with time after FSH treatment. However, in the case of antral follicles, there was no significant change in the ratio. The degenerating follicles contained apoptotic granulosa cells, macrophage, and polymorphonuclear leukocytes in the follicular cavity. The present results suggest that follicular degeneration caused by FSH hyperstimulation could be mediated by apoptosis as well as the acute inflammation.

• Biomolecules & Therapeutics
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• v.23 no.2
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• pp.174-179
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• 2015

BP201, porcine lung tissue-derived phospholipids, consists of phosphatidylcholine as a major phospholipid species. BP201 promoted hair growth after application onto the shaved backs of BALB/c and C3H mice. Its effect was enhanced when applied together with minoxidil (MNX) in C3H mice. When the tissue specimens prepared from the shaved skins of BP201-treated and control mice were microscopically examined, the total numbers of hair follicles in both anagen and telogen phases of BP201-treated mice were significantly higher than those of control mice. The numbers of hair follicles in the anagen phase of BP201-treated mice were also higher than those of control mice. In combination with MNX, BP201 further increased the total number of hair follicles, but did not alter the percentage of hair follicles in the anagenic phase. BP201 also increased the proliferation of human hair follicle dermal papilla cells. Collectively, BP201 possesses hair growth promoting potential, which would suggest its use singly or in combination for hair growth products.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.777-784
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• 2001

Evaluation of the granulosa cell (GC) monolayers developed from small (<5 mm) and large (>5 mm) follicles on the meiotic competence of caprine oocytes during in vitro maturation was done in this study in comparison to the granulosa cell coculture. Ovaries were collected from the local abattoir and follicular contents were aspirated for the monolayer culture. For IVM the oocytes were collected by puncturing the nonatretic follicles (>4 mm). Results revealed that at the same seeding rate, small follicular granulosa cell monolayer achieved confluence 24-48 h earlier than large follicular granulosa cell monolayer. GC monolayers significantly p (<0.05) improved the rate of meiotic resumption and nuclear maturation (84.76% vs 74.74%) after 27 h of culture in comparison to GC coculture. Statistically there was no significant difference in the maturation rate between the caprine oocytes matured over small or large follicular GC monolayers. It is concluded from the present study that GC monolayers support better nuclear and cytoplasmic maturation of growing caprine oocytes which is evident by better maturation rate over GC monolayer as compared to the oocytes matured with GC coculture. Granulosa cells from small and large follicles can be used for IVM with more or less in the same efficiency after conditioning them with maturation media in 18-24 h before the onset of culture.

• Reproductive and Developmental Biology
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• v.37 no.1
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• pp.17-22
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• 2013

Although assisted reproductive technology is very useful to develop novel and therapeutic biomaterials for reproduction, research on molecular mechanism of folliculogenesis in pig is not clear. Therefore, the alteration of gene expression during follicular development in pigs was examined in this study. The expression of folliculogenesis-related genes was quantified in preantral ($250{\sim}300{\mu}m$) and antral (> $300{\mu}m$ in diameter) follicles, and overall gene expression was evaluated by a genome-wide microarray. The microarray results showed that 219 genes were differentially expressed, and of those, 10 and 22 known genes showed higher and less expression at the preantral stage than at antral stages, respectively. Among them, the expression of NR0B1, PPARG, GATA4, and ANXA2 genes related to folliculogenesis was validated by quantitative real-time PCR analysis. The expression of PPARG and GATA4 genes were increased at antral stages, but a significantly stage-specific increase (p<0.05) was only detected in annexin A2 (ANXA2) in antral-stage follicles. The expression of NR0B1 genes was increased at preantral stage and these patterns of gene expression were comparable to the results obtained by microarray analysis. We propose that the systematical regulation of genes supporting specific follicle stage should be employed for improved in-vitro folliculognesis.

• Clinical and Experimental Reproductive Medicine
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• v.16 no.1
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• pp.35-40
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• 1989

In order to study the follicular atretic mechanism in mammalian ovary, the relationship between pyknotic index (PI) of granulosa cells and the steroid concentrations in the follicular fluid of atretic follicle was investigated. Follicles were isolated from porcine ovary according to their sizes and the reproductive phases. Steroid concentrations were quantified by high-performance liquid chromatography. As PI increased, the concentration of progesterone was significantly increased(p<0.05), whereas testosterone and estradiol showed no significant changes in their concentration. As follicular size was increased, PI of follicular GC in the luteal phase was increased significantly(p<0.05) and the molar ratio of progesterone to testosterone was increased in the follicles of follicular phase. It can be concluded that progesterone accumulated in the follicular fluid as atresia of the follicles was progressed, and that PI of granulosa cells could be used as one of convenient and pratical criteria for the identification of follicular atresia.

• Clinical and Experimental Reproductive Medicine
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• v.39 no.3
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• pp.95-106
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• 2012

It has been revealed that multiple cohorts of tertiary follicles develop during some animal estrous cycle and the human menstrual cycle. To reach developmental competence, oocytes need the support of somatic cells. During embryogenesis, the primordial germ cells appear, travel to the gonadal rudiments, and form follicles. The female germ cells develop within the somatic cells of the ovary, granulosa cells, and theca cells. How the oocyte and follicle cells support each other has been seriously studied. The latest technologies in genes and proteins and genetic engineering have allowed us to collect a great deal of information about folliculogenesis. For example, a few web pages (http://www.ncbi.nlm. nih.gov; http://mrg.genetics.washington.edu) provide access to databases of genomes, sequences of transcriptomes, and various tools for analyzing and discovering genes important in ovarian development. Formation of the antrum (tertiary follicle) is the final phase of folliculogenesis and the transition from intraovarian to extraovian regulation. This final step coordinates with the hypothalamic-pituitary-ovarian axis. On the other hand, currently, follicle physiology is under intense investigation, as little is known about how to overcome women's ovarian problems or how to develop competent oocytes from in vitro follicle culture or transplantation. In this review, some of the known roles of hormones and some of the genes involved in tertiary follicle growth and the general characteristics of tertiary follicles are summarized. In addition, in vitro culture of tertiary follicles is also discussed as a study model and an assisted reproductive technology model.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.325-330
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• 2003

There exists considerable evidence that insulin-like growth factor-I (IGF-I) is involved in the regulation of ovulation rate and follicle development. IGF-I is believed to modulate the effects of gonadotropins on follicular growth and cell differentiation via paracrine and autocrine mechanisms. Therefore, this study was performed to relate the expression of IGF-I on ovaries and follicles with egg productivity at 60 wk. The egg productivity of 70 KNOC was recorded from 20 to 60 wk. Blood was taken every 10 wk and ovaries and follicles were taken at 60 wk. Serum IGF-I and IGF-I of ovaries and follicles were measured by radioimmunoassay. Based on egg production levels up to 60 wk and ovarian IGF-I expression at 60 wk, respectively. Chickens were divided into two groups, high and low. Egg production and serum IGF-I in the high IGF-I group were higher than those in the low group. Moreover, the IGF-I expression of follicles in the high ovarian IGF-I expression group was higher than that in the low group. These finding are consistent with the report that IGF-I indirectly regulates ovulation in chickens, suggesting that this regulation may play an important role in improved egg productivity.

• The Korean Journal of Zoology
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• v.8 no.2
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• pp.23-27
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• 1965

The present study is an analysis of some alterations occurring in the population of folliclesin the ovary treated with the gonadotrophins in intact and unilaterally ovariectomized mice. the differences between the findings inthe intact and semispayed animals and those in gonadotrophintreated intact and semispayed animals were disucssed. 1) When mice were semispayed at the stage of diestrus, the remaining ovary showed an increase of secondary follicles in number, while a decrease of atretic folicles, compared with those in intact animals. 2) After injection of PMS and HCG following semispaying at the diestrus stage, the remaining ovary contained larger number of secondary follicles and corpora lutea than those in semispayed animals with no treatment , while showed smaller number of atretic follicles. 3) It is sure that follicular development is remarkably accelerated in the intact mice treated with PMS and HCG. 4) The effect of PMS and HCG on the follicular development was gradually decreased with time in the intact and semispayed animals afte rexogenous hormone therapy. 5) It is believed in the experiment that a decrease of follicular atresia in number and an increase of secondary follicles may be responsible for compensatory reaction after semispaying.

• Journal of Veterinary Clinics
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• v.27 no.1
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• pp.46-49
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• 2010

In this study, we investigated the number of follicles, oocyte recovery rate and oocyte competence after in vitro maturation according to the size of follicle. And equine oocyte competence after in vitro maturation was investigated in terms of the diameter of follicle with criteria of maturation: nuclear stage after Hoechst staining. The average number of follicles per ovary with middle size (11-20 mm, 2.68) was higher than those of small (5-10 mm, 0.74) and large size follicle (> 21 mm, 1.63), therefore medium follicle (53.1%) had higher proportion than other size of follicles. The average numbers of follicle per ovary was 5.05. The rate of oocyte recovery in small (54.5%) and middle follicle (50%) was higher than that in large follicle (40.9%). After culture for 48 h in Medium 199, 50%, 45.5%, and 44.4% of oocytes from the follicles with diameters of 5-10, 11-20, > 21 mm, respectively reached the metaphase II stage. This is the first report showing number of follicle, oocyte recovery rate according to follicular size, and in vitro oocyte maturation in Jeju mare in Korea. To fulfill in vitro equine embryo production, further studies such as the seasonal effect, in vitro fertilization etc is need.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.1
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• pp.40-49
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• 2019

Chronic and unpredictable stress can disrupt the female reproductive system by suppression for secretion of gonadotrophin-releasing hormone (GnRH) and gonadotrophin, resulted in ovarian malfunction and infertility. In the recent days, kisspeptin has been highly highlighted as a hypothalamic peptide which directly stimulates synthesis and release for GnRH. However, in spite of the key role of kisspeptin in the female reproductive system, little information is still available on the changes of its expression during ovarian cycle under stressed condition. Therefore, we induced chronic and unpredictable stress series to the female mice to analyze kisspeptin expression in the brain and ovary. Stressed mice exhibited changes of behavior and body weight gain during the stress assessment, which suggested that the present stress model in mice was successfully established. In the brain level, kisspeptin expression was attenuated than control. In the ovary level, the stressed mice displayed irregularly shrunk oocytes with broken zona pellucida throughout the follicle stages, pyknotic granulosa cells, decreased number of developing follicles and increased number of atretic follicles than the control. In case of kisspeptin expression in the whole ovary tissue, the expression level was decreased in the stressed mice. In detail, the less intensity of kisspeptin expression in the antral follicles phase was observed in the stressed mice than control mice, indicating that local function of kisspeptin during ovary cycle is highly associated with development of ovarian follicles. We expect that the present study has important implications for the fields of reproductive biology.