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Updated: May 27, 2026

Analysis of Chromosome Segregation, Histone Acetylation, and Spindle Morphology in Horse Oocytes
Published on: May 11, 2017
Heme oxygenase-1 expression in the ovary dictates a proper oocyte ovulation, fertilization, and corpora lutea
Maria L Zenclussen1, Federico Jensen, Sofia Rebelo
1Department of Experimental Obstetrics and Gynecology, Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany.
Problem:
Animals deficient in Heme oxygenase-1 (HO-1, Hmox1(-/-) mice) have impaired pregnancies, characterized by intrauterine fetal death. HO-1 expression has been shown to be essential for pregnancy by dictating placentation and intrauterine fetal development. Its absence leads to intrauterine fetal growth restriction and fetal loss, which is independent of the immune system. Defect in previous steps, e.g., ovulation, may, however, also count for their poor reproductive outcome.
Method Of Study:
Here, we investigated ovulation after hormonal hyperstimulation in Hmox1 wild-type and knockout animals.
Results And Conclusions:
We observed that animals lacking HO-1 produced significantly less oocytes after hormonal stimulation than wild type animals and this was mirrored by the number of corpora lutea in the ovary. Furthermore, ovulated oocytes from Hmox1(-/-) animals were poorly fertilized compared with those from wild-type animals. In conclusion, we demonstrate here that HO-1 plays a pivotal role in the process of oocyte ovulation as well as fertilization, bringing to light a new and unsuspected role for HO-1.
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