[Intracellular localization of calcium in loach embryonic cells at the early gastrula stage]

Intracellular localization of calcium-accumulated structures in the loach embryo cells at the state of early gastrulation was determined by electron microscope histochemical pyroantimonate method. Calcium-precipitate was observed in the nucleus (external and inner membranes, chromatin and nucleolus), and in the cytoplasm (ER, mitochondria and submembrane cortical layer). Our present data show that such cell organelles as nuclear envelope, ER, and mitochondria serve as the basic cellular stores for calcium, confirming the existence of calcium signal system both in the nucleus and in the cytosol.