논문 상세보기
pp.35-43
이온 통로 및 이온 농도의 변화는 수정 현상을 포함한 다양한 세포 기능에 중요한 역할을 한다. 그러나 이러한 이온의 변화가 포유동물 배의 발달과정에 어떻게 관여하는지에 대해서는 알려진 바가 적다. 본 연구에서는 생쥐난자가 수정 이후 배 발달 과정을 거치는 동안 나타나는 칼슘과 포타슘 이온의 변화를 전기생리학적 실험 기법과 공초점 현미경을 이용하여 조사하였다. 수정 시에 나타나는 일시적인 세포내 칼슘 농도 변화는 활성 전류(수정 전류)와 함께 동반되었다.
Ions play important roles in various cellular processes including fertilization and differentiation. However, it is little known whether how ions are regulated during early embryonic development in mammalian animals. In this study, we examined changes in concentrations in embryos and oviduct during mouse early embryonic development using patch clamp technique and confocal laser scanning microscopy. The intracellular calcium concentration in each stage embryos did not markedly change. At 56h afier hCG injection when 8-cell embryos could be Isolated from oviduct, concentration in oviduct increased by 26% compared with that at 14h after injection of hCG During early embryonic development, membrane potential was depolarized (from -38 mV to -16 mV), and currents decreased, indicating that some channel might control membrane potential in oocytes. To record the changes in membrane potential induced by influx of in mouse oocytes, we applied 5 mM to the bath solution. The membrane potential transiently hyperpolarized and then recovered. In order to classify channels that cause hyperpolarization, we first applied TEA and apamin, general channel blockers, to the bath solution. Interestingly, the hyperpolarization of membrane potential still appeared in oocytes pretreated with TEA and apamin. This result suggest that the channel that induces hyperpolarization could belong to another channel such as two-pore domain channel that a.e insensitive to TEA and apamin. From these results, we suggest that the changes in concentrations play a critical role in cell proliferation, differentiation and reproduction as well as early embryonic development, and channels could be involved in regulation of membrane potential in ovulated oocytes.
