Abstract
Objectives: Ca2+ is critical for normal oocyte activation and fertilization, and any alteration to the Ca2+ homeostasis may lead to failed fertilization or even cell death. It has been shown that intracellular Ca2+ is increased in bovine and human oocytes when cultured in vitro. Additionally, ATP sensitive potassium channels have been characterised recently in human and Xenopus oocytes Glibenclamide a KATP channel blocker was shown to protect human oocytes from Ca+2 overloading. None of these studies have been conducted in mouse oocytes to determine if they are a suitable alternative to human oocytes in the research setting. Thus, this research note aims to demonstrate if cryopreserved metaphase II (MII) mouse oocytes show similar Ca+2 and plasmalemmal membrane potential dynamics to those in human oocytes. Also, to show if glibenclamide influences Ca+2, and plasmalemmal membrane potential in cryopreserved metaphase II mouse oocytes. Results: our data did not show an increase in intracellular Ca2+ in untreated cryopreserved mouse oocytes loaded with Fluo-3 AM dye. However, an increase in the plasmalemmal membrane potential was noticed (hyperpolarization). Glibenclamide has shown no significant effect on Ca+2, mitochondrial and plasmalemmal membrane potential.
SUCCESS RATES OF RESCUE ICSI THE DAY AFTER FAILED FERTILIZATION IN CONVENTIONAL INSEMINATION: FRESH VERSUS FROZEN EMBRYO TRANSFERS
