Objectives: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age. Polycystic ovary (PCO) is a criterion for PCOS. Several animal models of polycystic ovary morphology (PCOM) are developed in order to study PCOS aspects. The present study aimed to develop a polycystic ovarian model in mice.Materials and Methods: Thirty-four young adult female mice were divided equally into estradiol valerate (EV) treated and control groups. Mice in experimental group (n=18) received a single dose injection of EV (IM, 4 mg/kg). Weight and fertility rate of all mice were recorded. Morphology of ovarian follicles was assessed too. Chi-square and independent t test were used for comparison between groups. P value less than 0.05 was considered as significant level.Results: After 60 days, the weight of EV-treated mice was significantly lower than control (P<0.04) and the experimental group did not show any significant changes in their body weight. Fertility rate in experimental group was significantly lower (P<0.001) than the other group. Follicle count showed that the number of preovulatory follicles and corpora lutea were lower (P<0.001) and atretic follicles were higher (P<0.001) significantly in EV-treated group in comparison to control. However, there were no significant differences in the number of primary, preantral and antral follicles between two groups.Conclusion: The polycystic ovary morphology can be induced in adult mice with a single dose of EV. This model may help to improve our knowledge on all aspects of PCOS.

In this study, microspheres containing estradiol valerate were prepared by solvent evaporation method using poly (glycolide-co-lactide) (PLGA 50:50) and poly (lactide). The effect of different process variables such as polymer type, drugpolymer ratio, stirring rate, volume of internal phase and temperature of external phase on the morphology, particle size distribution, encapsulation efficiency and in vitro release profile were investigated. All microspheres had spherical shape with smooth surface. Increasing the internal phase volume and decreasing the external phase temperature resulted in smaller particles. At low drug loadings, PLGA microspheres were larger than PLA ones. Changing the theoretical drug loading from 5 to 20% decreased the drug release rate from PLGA microspheres whereas the result for PLA microspheres was the opposite.

For the present study, and follow-up of histochemical changes in estradiol valerate-induced polycystic ovary syndrome (PCOS), 48 virgin 90-day-old female rats were used. The rats were divided into the treatment and control groups. For each rat of the treatment group, 4 mg estradiol valerate was injected through intramuscular route for the induction of PCOS. The control group was taken the same amount of sterile sesame oil. After 63 days of hormone administration, all rats were sacrificed and their ovaries were collected immediately and processed for histochemical studies. These studies were consisted of localization of carbohydrate using PAS method, saturated and unsaturated lipids using Oil-Red-O and Sudan Black B, lipase and alkaline phosphatase. The PAS reaction was seen in some structures of the atretic and cystic follicles such as on zona pellucida (ZP), basement membrane of granulosa cells, connective tissue fibers of ovarian stroma, follicular fluid and granulose cells. This reaction was enhanced in basement membrane of granulose cells of cystic follicles. The lipid droplets were seen in follicular structures of both the atretic and cystic follicles. The presence of macrophages was confirmed in cystic ovaries by this study. The lipase reactions were seen in granulose and theca cells of atretic and cystic follicles. The lipase reaction in the theca layer of cystic follicles was stronger than in the granulose cell layer of such follicles. The alkaline phosphatase reaction was seen in the theca and granulose cells of atretic and cystic follicles and by the progression of these processes and cystic follicle formation, the reaction was increased accordingly. We concluded that, during follicular atresia and cystic follicle formation, histochemical alterations are occurred in follicular structures.