Category Archives: Follicle

The proportions of follicles in the early primary stage of development in untreated and recombinant mouse KITL-treated (50 ng/ml and 150 ng/ml) ovaries were not significantly different from each other. Despite a trend toward increased number, there was no significant difference in the proportions of primary and preantral follicles with 50 ng/ml recombinant mouse KITL. However, treatment with 150 ng/ml recombinant mouse KITL significantly (P < 0.05) increased the proportions of primary and preantral follicles (15.7% 6 1.8% and 8.6% 6 1.4%, respectively), compared with untreated cultured ovaries (5.0% 6 0.9% and 2.3% 6 0.5%, respectively) (Fig. 8). (more…)

The addition of neutralizing antibody to the culture media partially inhibited the spontaneous activation of primordial follicles. This was manifested by a significant (P < 0.05) increase in the proportion of primordial follicles in neutralizing antibody-treated ovaries (47.2% 6 3.6%) compared with untreated ovaries (33.0% 6 3.2%) (Fig. 8). This increase in the proportion of primordial follicles was reflected by a decline in the proportions of early primary, primary, and preantral follicles in the antibody-treated group compared with the untreated culture control group, although the differences between these two treatment groups within individual follicle stages were not statistically significant. (more…)

Therefore, recombinant mouse KITL did not enhance the survival of follicles in neonatal mouse ovaries maintained in vitro, nor did KITL-neutralizing antibody promote follicular atresia. (more…)

Recombinant mouse KITL (50 ng/ml and 150 ng/ml) had no stimulatory effect on the diameter of oocytes in the preantral follicle population compared with untreated cultured explants (Table 1). (more…)

Comparisons of oocyte sizes between untreated and recombinant mouse KITL-treated cultured explants were made in order to assess the effect of exogenous recombinant mouse KITL on oocyte growth in vitro. Recombinant mouse KITL was shown to have a major effect on the size of oocytes at the earliest stages of development (Table 1). The mean diameter of primordial follicle oocytes increased significantly (P < 0.05), from 31.7 6 0.2 im in untreated cultured explants, to 34.6 6 0.3 im in explants treated with 50 ng/ml recombinant mouse KITL, to a final diameter of 36.3 6 0.1 im in 150 ng/ml recombinant mouse KITL-treated explants (Table 1). (more…)

In order to determine whether endogenous KITL had a role in promoting the growth of oocytes from primordial and early primary follicles that was observed during in vitro culture, neutralizing antibody to recombinant mouse KITL was added to the culture media. It was anticipated that if endogenous KITL were inducing growth in follicles maintained in vitro, then neutralization of the ligand would result in primordial and early primary follicle diameters comparable to those in preculture tissues. (more…)

However, there was an increase in the proportions of primary and preantral follicles compared with untreated and recombinant mouse KITL-supplemented explants, although this difference was not statistically significant in all pairwise comparisons (Fig. 6). These data suggest that the inhibitory antibody possibly enhances receptor signaling. (more…)

To determine whether endogenous KITL was responsible for the spontaneous activation of primordial follicles, rabbit ovarian cortical explants were treated with KITL-neutralizing antibody. There was no change in the developmental distribution of follicles in explants treated with neutralizing antibody compared with untreated cultured explants (Fig. 6). Therefore, neutralizing antibody did not prevent spontaneous follicle activation. (more…)

Following 8 days of culture in vitro, the developmental distribution of follicles in cortical explants changed significantly (P < 0.05). In untreated cultured explants, the primordial follicle population decreased to comprise only 25.2% 6 2.7% of all of the follicles present, and the percentages of early primary, primary, and preantral follicles increased significantly (P < 0.05) to 58.1% 6 1.4%, 11.6% 6 1.4%, and 5.2% 6 0.8%, respectively (Fig. 6). These data indicate that a large proportion of rabbit primordial follicles spontaneously activate and develop in vitro. (more…)

Effects of Culture and Recombinant Mouse KITL Treatment on the Survival of Follicles in Rabbit Ovarian Cortical Explants In preculture rabbit ovarian cortical explants, follicles were generally healthy and showed no signs of atresia. Following 8 days in vitro, approximately 50% of follicles exhibited signs of degeneration (Fig. 5). However, the proportion of total follicles that were healthy in the rabbit ovarian cortical explants did not differ significantly between the cultured treatment groups (Fig. 5). These results indicate that follicle survival was not enhanced by recombinant mouse KITL (50 ng/ml and 150 ng/ml), nor was follicular atresia promoted when the KITL/KIT interaction was inhibited by KITL-neutralizing antibody. (more…)