Exploring the presence of female germline stem cells in rats and mice

Objective: To determine the presence of female germline stem cells (FGSCs) in postnatal mammals under physiological and pathological conditions. Methods: We explored the presence of FGSCs using various models, including mice of different ages, an ovarian mouse model with mechanical injury, and a rat model of endometriosis. Moreover, we investigated the feasibility of inducing FGSCs in vitro using cultured ovarian tissues and employed the differential adhesion method for isolating FGSCs. For labeling FGSCs within the ovary, we employed markers such as mouse VASA homolog (MVH)/ubiquitin carboxy-terminal hydrolase L1 (UCHL1) and 5-Bromo-2'-deoxyuridine (BrdU). Results: Our investigations revealed that FGSCs were not detectable in any of our models, across all conditions tested. Conclusion: Our experiments provide evidence for the viewpoint that no FGSC exists in the ovaries of postnatal mice or rats, and then support that mammalian ovaries do not produce new oocytes after birth.