[The genesis and reactive changes of mitochondria at different functional phases of the cell]

At ultrastructural level ways of formation and proliferation of mitochondria have been followed in rat lutein cells and interstitial endocrine cells of the corpus luteum at various stages of its development. During mitosis and at increased function of the lutein and interstitial cells mitochondria are formed de novo. At a certain change of the cell functional state, mitochondria proliferate by means of division or budding.