Involvement of Ca2+ signaling pathway during oocyte maturation of the northern quahog Mercenaria mercenaria.

摘要

In many molluscs, it has been found that Ca2+ signaling pathway is involved in the resumption of meiotic maturation in oocytes. To better understand the possible role of Ca2+ signaling pathway in regulating meiotic maturation in oocytes of the northern quahog Mercenaria mercenaria, free extracellular Ca2+, A23187 (calcium ionophore), verapamil (calcium channel blocker), and trifluoperazin (calmodulin antagonist) were used to incubate oocytes or serotonin-induced oocytes by pharmacological methods. Results show that extracellular Ca2+ (50-10 micro M) and A23187 (1-10 micro M) can stimulate the meiotic maturation. In addition, verapamil (1-100 micro M) and trifluoperazin (10-1,000 micro M) could inhibit serotonin-induced oocyte maturation. Therefore, Ca2+ is essential for the reinitiation of meiotic maturation in oocytes of the northern quahog. Moreover, an increase in [Ca2+]i can promote meiotic maturation.