Oxytocin induces embryonic diapause

Area of Science:

• Reproductive biology
• Developmental biology
• Endocrinology

Background:

• Embryonic diapause, a temporary developmental arrest before implantation, occurs in various species.
• Facultative diapause is linked to maternal metabolic stress, such as during nursing.
• The natural inducing factor for embryonic diapause remained unidentified.

Purpose of the Study:

• To identify a natural inducing factor for embryonic diapause.
• To investigate the role of oxytocin in regulating embryonic diapause in mice.

Main Methods:

• Induction of gestational delays via nursing or optogenetic stimulation of oxytocin neurons.
• Analysis of oxytocin receptor expression in mouse blastocysts.
• In vitro culture of embryos with oxytocin to observe developmental effects.
• Assessment of embryo survival rates in oxytocin receptor-knockout models.

Main Results:

• Oxytocin administration or stimulation of oxytocin neurons triggered gestational delays mimicking diapause.
• Mouse blastocysts were found to express oxytocin receptors.
• Oxytocin exposure induced delayed implantation-like dispersion in cultured mouse embryos.
• Embryos lacking oxytocin receptors exhibited reduced survival rates during diapause.

Conclusions:

• Oxytocin is identified as a natural inducer of embryonic diapause in mice.
• Oxytocin plays a crucial role in coordinating embryonic development with uterine conditions during pregnancy.
• This mechanism represents an evolutionarily conserved strategy for ensuring reproductive success.