Remission of the polycystic ovarian condition (PCO) in the rat following hemiovariectomy

Convery, Margaret; McCarthy, Gerald F.; Brawer, James R.

doi:10.1002/ar.1092260309

Cited by 23 publications

(22 citation statements)

References 14 publications

(27 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In studies on EV-and E 2 -treated rats also, corpora lutea were not found [11,14]. In the present experiments on guinea pigs, few corpora lutea were found in the overtly cystic condition.…”

Section: Discussioncontrasting

confidence: 67%

See 1 more Smart Citation

Induction by Estradiol-17β of Polycystic Ovaries in the Guinea Pig1

Quandt

Hutz

1993

Biology of Reproduction

View full text Add to dashboard Cite

In the present study we wished to develop a model for polycystic ovarian syndrome (PCOS) using the guinea pig, because this animal's cycle, compared to other rodent models, more closely emulates that of humans. Four silastic capsules, either empty or containing cholesterol or estradiol-17 beta, were placed subcutaneously for 48 h on Day 10 or 12 of the cycle. Vaginal smears were taken daily. Cardiac blood was drawn at various intervals. At necropsy, trunk blood was collected and ovaries were excised and analyzed histologically. Cycle length was extended over that in controls in animals treated with estradiol-17 beta (E2) on Day 12 of the cycle. Treatment with E2 resulted in an increase in serum estrogen 2 h after capsule insertion. No changes were evident in progesterone or androstenedione concentrations with treatment. Animals treated with E2 and killed late (54 days after capsule removal) showed cysts grossly (group A), while occult cysts were present in E2-treated animals killed early (17 days; group B); no cysts were observed in control groups. Ovarian weight and size were increased in group A over controls. There was an increase in the fraction of atretic:total follicles < 500 mm in size in group A compared to group B as well as compared to controls. Since these results are similar to those seen in human PCOS, we conclude that the guinea pig may serve as an exceptional and unique model for the study of PCOS and may be applicable to humans.

show abstract

“…In studies on EV-and E 2 -treated rats also, corpora lutea were not found [11,14]. In the present experiments on guinea pigs, few corpora lutea were found in the overtly cystic condition.…”

Section: Discussioncontrasting

confidence: 67%

“…EV-and E 2 -treated rats exhibit cysts that resemble the human condition [11,14]. The situation in guinea pigs is also similar to that in both humans and rats.…”

Section: Discussionsupporting

confidence: 59%

Induction by Estradiol-17β of Polycystic Ovaries in the Guinea Pig1

Quandt

Hutz

1993

Biology of Reproduction

View full text Add to dashboard Cite

show abstract

“…Due to this intermediate status, some studies have postulated that this type of follicle (those that still possess oocytes) intensely binds hCG (Brawer et al 1989) and can be rescued from this status and be ovulated (Brawer et al 1989, Convery et al 1990). Therefore, it is possible that type III follicles originate from the antral preovulatory follicles.…”

Section: Kp and Ovulationmentioning

confidence: 99%

Kisspeptin is involved in ovarian follicular development during aging in rats

Fernandois¹,

Na²,

Cuevas³

et al. 2015

Journal of Endocrinology

View full text Add to dashboard Cite

We have previously reported that kisspeptin (KP) may be under the control of the sympathetic innervation of the ovary. Considering that the sympathetic activity of the ovary increases with aging, it is possible that ovarian KP also increases during this period and participates in follicular development. To evaluate this possibility, we determined ovarian KP expression and its action on follicular development during reproductive aging in rats. We measured ovarian KP mRNA and protein levels in 6-, 8-, 10-and 12-month-old rats. To evaluate follicular developmental changes, intraovarian administration of KP or its antagonist, peptide 234 (P234), was performed using a mini-osmotic pump, and to evaluate FSH receptor (FSHR) changes in the senescent ovary, we stimulated cultured ovaries with KP, P234 and isoproterenol (ISO). Our results shows that KP expression in the ovary was increased in 10-and 12-month-old rats compared with 6-month-old rats, and this increase in KP was strongly correlated with the increase in ovarian norepinephrine observed with aging. The administration of KP produced an increase in corpora lutea and type III follicles in 6-and 10-month-old rats, which was reversed by P234 administration at 10 months. In addition, KP decreased the number and size of antral follicles in 6-and 10-month-old rats, while P234 administration produced an increase in these structures at the same ages. In ovarian cultures KP prevented the induction of FSHR by ISO. These results suggest that intraovarian KP negatively participates in the acquisition of FSHR, indicating a local role in the regulation of follicular development and ovulation during reproductive aging.

show abstract

“…The follicles were counted and classified as healthy or atretic (Brawer et al 1986, Convery et al 1990. Preantral follicles were defined as follicles without any antral cavity and with two or more layers of granulosa cells.…”

Section: Study Proceduresmentioning

confidence: 99%

The New Zealand obese mouse model of obesity insulin resistance and poor breeding performance: evaluation of ovarian structure and function

Radavelli-Bagatini

Blair²,

Proietto³

et al. 2011

Journal of Endocrinology

View full text Add to dashboard Cite

Infertility, associated with oligo/anovulation, increased ovarian volume, numerous follicular cysts, and metabolic disturbances such as obesity and insulin resistance (IR) are characteristics common to polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age. Here, we show that New Zealand obese (NZO) mice display similar metabolic characteristics such as obesity, leptin insensitivity, glucose intolerance, and IR. Importantly, NZO mice are poor breeders; however, the mechanism for this has not been investigated. The aim of this study was to assess the ovarian structure/morphology and sex hormone levels in female NZO and lean C57BL/6J control mice. Twenty-five NZO and twenty female control mice were studied at three different ages (young, adult, and aged). The animals were weighed, an insulin tolerance test was carried out, and blood was collected for measurement of hormone levels. The ovaries were removed for histological analysis. As expected, NZO mice presented higher body weights (PZ0 . 001), increased basal plasma glucose (PZ0 . 007), and insulin levels (PZ0 . 001) as well as IR, compared with control mice. NZO mice showed an increased ovarian volume, reduced numbers of corpora lutea, and higher total follicle numbers (PZ0 . 0001). The number of primordial follicles increased (PZ0 . 02) at the young stage, as well as the amount of atretic follicles (PZ0 . 03), in NZO compared with control mice. NZO mice also displayed reduced plasma LH and increased estradiol levels. In conclusion, NZO mice show a poor breeding performance due to decreased ovulation, increased number of primordial and atretic follicles, and ovarian size. Given that NZO mice are obese, hyperinsulinemic and insulin resistant, they are suitable for investigating pathophysiological mechanisms linking metabolic alterations with reproductive defects.

show abstract

Remission of the polycystic ovarian condition (PCO) in the rat following hemiovariectomy

Cited by 23 publications

References 14 publications

Induction by Estradiol-17β of Polycystic Ovaries in the Guinea Pig1

Induction by Estradiol-17β of Polycystic Ovaries in the Guinea Pig1

Kisspeptin is involved in ovarian follicular development during aging in rats

The New Zealand obese mouse model of obesity insulin resistance and poor breeding performance: evaluation of ovarian structure and function

Contact Info

Product

Resources

About