The aim of this study was to investigate the effect of applying the 1-mT magnetic field (MF) in the ovarian tissue vitrification.
Materials and methods
Ovaries of 6-8 week-old Naval Medical Research Institute female mice randomly were divided into 5 groups: V1: Ovaries that immediately after leaving of the mice body, were examined histologically (control group), V2: Ovaries that without exposure to MF were frozen and thawed, V3: Ovaries that were frozen by exposure to MF, V4: Ovaries that were melted by exposure to MF and V5: Ovaries that by exposure to MF were frozen and thawed. Vitrified-warmed samples were incubated for 30 minutes and fixed in Bouin’s fixative. The samples were serially sectioned and stained either with H&E or immunohistochemistry kit of pro-caspase-3.
The difference in the number of primordial, primary and preantral healthy and dead follicles between the control and V4 groups was not significant. Morphologically healthy antral follicles showed significant reductions in all vitrification groups compared to the control. In comparison with healthy follicles, there were significantly more dead follicles in the V2 group than the control group.The apoptotic follicles increased significantly after vitrification, with the exception of the antral follicles.
Results confirmed that, MF-exposed follicles exhibited greater resistance to the freezing and thawing. Thus, it is reasonable to suggest that the 1mT MF exposure reduce the damage of the ovarian tissue during vitrification and helpful for ovarian cryopreservation.