Regeneration of vital organs of mammals in fetal period

Abstract

BACKGROUND: This study is relevant owing to the importance of fetal regeneration of pathologically altered organs in mammals for fundamental science and practical medicine. AIM: To elucidate the regenerative potential of the cardiac, brain, and liver tissues in fetuses during fetal development following mechanical trauma. MATERIALS AND METHODS: As experimental animals, 12 mature female chinchilla rabbits weighing 39004350 g and 30 outbred female rats weighing 265280 g were examined. Mechanical trauma to the heart and brain was inflicted on rabbit fetuses (n=50) and to the liver of rat fetuses. The operated fetuses (n=84) were withdrawn from the experiment 1, 3, 5, 7, 9, 11, 15, and 30 days after the operation. Histological, morphometric, electron microscopic, and immunohistochemical methods were employed. RESULTS: Following the healing of mechanical trauma in the heart of rabbit fetuses, the necrotic area was completely restored. In rate fetuses, the liver did not fully regenerate, and the fibrotic area at the site of the dead tissue only decreased. The brain of rabbit fetuses did not fully recover, and a glial scar appeared in the place of the dead tissue. The difference in the healing outcomes of organ damage in fetuses is associated with the absence of an exudative reaction to injury in the heart of rabbit fetuses, whereas in rat fetuses, this reaction occurred during injury. In the nervous tissue, the activation of the protein synthetic function of neurocytes was recorded, which can be regarded as a sign of intracellular regeneration. CONCLUSIONS: The results suggest that the vital organs of mammalian fetuses have high regenerative potencies.