Calcium (Ca²⁺) expression and intensity in cumuluc-oocyte complex(COCs) in Kacang goat after vitrification

The process of vitrification of the cumulus-oocyte complex (COCs) often results in cold shock. When warming, heat shock occurs which can disrupt the balance of intracellular calcium (Ca²⁺) intensity. Drastic changes in temperature cause Reactive Oxygen Species (ROS), affecting changes on Ca²⁺in COCs. The role of calcium is needed for oocyte activation in the fertilization process. The purpose of this study was to measure the expression of Ca²⁺and the intensity of Ca²⁺in COCs after vitrification. The study was divided into 2 groups, the control group (C) of fresh COCs, and the treatment group (T) of COCs after vitrification. After vitrification for 24 hours, then thawing, the expression of Ca²⁺was examined using the Immunocytochemistry (ICC) method and the intensity of calcium (Ca²⁺) with a Confocal Laser Scanning Microscope (CLSM). The research data obtained were analyzed statistically by T-Test. The results showed that the expression of Ca²⁺in the control group (12.00±0.00) was different from the treatment group (0.35±0.79). The intensity of Ca²⁺in the control group (1059.43±489.59) was different from the treatment group (568.21±84.31). The conclusion of this study is that cryopreservation affects calcium in COCs; there were differences in the expression and the intensity of Ca²⁺between fresh COCs and COCs after vitrification. Ca²⁺intensity of COCs after vitrification was concentrated in the nucleus, while in fresh COCs it was concentrated in the cytoplasm.