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Different animal models of polycystic ovary syndrome (PCOS) are introduced but most of them are induced by exogenous chemical or hormonal manipulation. The aim of the present study was to evaluate histomorphometric characteristics of ovaries in primiparous and nulliparous PCOS rats which were exposed to 90 days constant fluorescent light. Twenty-four adult female primiparous and nulliparous rats were divided into two subgroups of light exposure and control (n = 6). Both light exposure groups were exposed to 90 days constant 24 h per day light with the intensity of 350 Lx to 1 m2 on floor. Ovaries of all rats were histomorphometrically evaluated after 90 days. The following indices were calculated and compared between groups: ovary volume, stroma volume, total follicular volume, number of secondary follicle, number of tertiary follicle, mean of tertiary follicle volume, corpus luteum volume, number of corpus luteum, and mean of corpus luteum volume. Serum testosterone concentrations were measured. In both primiparous and nulliparous rats, ovary volume and number and volume of corpora lutea of control groups were more than of light exposure groups (P

Objective: To study the effects of anestrus dog serum in rodents (contains high amount of FSH) compared with two common superovulatory programs. Methods: Rats (n=30) at diestrus phase were evenly divided into pregnant mare serum gonadotrophins (PMSG) group (administrated with 30 IU PMSG, and 48 h later following by 25 IU hCG), recombinant follicle stimulating hormone (rFSH) group (reducing dose every 12 h from 5 to 1 IU, then following by 25 IU hCG) and anestrus dog serum group (reducing dose every 12 h from 0.6 to 0.1 mL, then following by 25 IU of hCG). Mice (n=30) were also evenly divided into PMSG group (5 IU PMSG used at 13 pm, and 48 h later following by 5 IU of hCG), rFSH group (from 13 pm, reducing dose every 12 h from 2.5 to 0.5 IU, then following by 5 IU hCG) and anestrous dog serum group (from 13 pm, reducing dose every 12 h from 0.100 to 0.025 mL, then following by 5 IU hCG). Mice and rats placed with males for 24 h after last injection. Histology samples of ovaries were prepared and the numbers of corpus lutea were counted on day 14 after mating. Results: In mice, the differences among mean number of corpus lutea in all groups (P=0.01) and between FSH and dog serum group were significant (P=0.000 7). But no significant differences were found between the mean number of corpus lutea in dog serum and PMSG, or between FSH and PMSG groups. In rats, mean number of corpus lutea were significant differences among three groups (P=0.01), and between PMSG and dog serum groups (P=0.02). Conclusions: Superovulatory response in anestrus dog serum group is similar to PMSG group in mice, which is relatively similar to FSH in rats.

The following experiments were designed to examine the effect of serum of spayed dogs on superovulation response in mice and rats. In Experiment 1, female mice at diestrus (n=30) were divided into three equal groups and superovulated with either administration of 5 IU pregnant mare serum gonadotropin (PMSG) or recombinant follicle stimulating hormone (rFSH) (reducing dose from 2.5 to 0.5 IU) and 5 IU human chorionic gonadotropin (hCG) administered 48h later. Serum of spayed dogs was administered intraperitoneally at a reduced dose from 0.1 to 0.025 mL in a 48 h period. In Experiment 2, female rats (n=30) at diestrus stage were divided into three equal groups. Superovulation was induced using either 30 IU PMSG, or a dose reduced from 5 to 1 IU rFSH and 25 IU hCG administered 48h later. Serum of spayed dogs was administered in a reduced dose from 0.6 to 0.1 mL in a 48 hour period. Female mice and rats were mated 24 h following hCG administration. On day 14 after mating, animals were euthanized and ovarian sections were fixed for histopathological evaluation and corpus luteum (CL) counting. No significant difference observed in mean (±SEM) number of CLs between the PMSG group and the mice that received serum of spayed dog (10.4±1.3 vs 9.2±1.0). Mean (±SEM) number of CLs tended to be lower in rats that received serum of spayed dog than those of rats which received either PMSG or rFSH (15.1±1.9 vs 23.6±3.1 and 23.1±2.9, P=0.06, respectively). In conclusion, serum of spayed dogs is able to induce a superovulatory response in mice and rats.

Background: Hypothalamic Melanocortin-4 Receptor (MC4R) and kiss1/kisspeptin systems play roles in reproductive processes. This study was conducted to evaluate changes in MC4R and kiss1 genes expression in the arcuate nucleus (ARC) of the hypothalamus and its relationship with polycystic ovary syndrome (PCOS) in rats.Materials and Methods: In the current experimental study, 24 female rats were randomly and equally allocated into nulliparous and primiparous groups and then were divided into two subgroups of PCOS and control. PCOS was induced by exposure to continuous light. Sex-related hormones were evaluated by radioimmunoassay or immunoradiometric assay. Expressions of MC4R and kiss1 gene in the ARC of the hypothalamus of the rats were evaluated by real-time PCR. Histomorphometric alterations of ovaries were compared between groups.Results: Number of tertiary follicles and their size and number of atretic follicles in the PCOS subgroups were more than those in the controls (P0.05).The kiss1 mRNA expression in the PCOS and control subgroups was not significantly different (P>0.05).Conclusion: Overexpression of MC4R gene after PCOS induction in the ARC of the hypothalamus may link to metabolic disorders of induced PCOS in the rats. However, alteration in the kiss1 mRNA expression after PCOS induction was not observed in the rats. [GMJ.2018;7:e1070]

This paper reports a case of super pregnancy in a BALB/c mouse pregnant with 30 pups following induction of superovulation using a PMSG-hCG protocol. Superovulation was induced in 10 mice by injecting 5 IU PMSG followed by 5 IU hCG 48 hours later. Immediately after injection of hCG, animals were placed with males at a ratio of 1 to 1 for 24 hours. On day 14 after mating, animals were killed by cervical dislocation and the uterus was examined for pregnancy and the number of fetuses. The mean (±SEM) number of fetuses observed in ten mice was 5.4±3.18 with an unexpectedly super pregnant mouse bearing 30 fetuses on day 14 of pregnancy.