[Adaptive responses of the secretory cardiomyocytes of the right atrium during simulation of the long-term and repeated gravity by antiorthostatic suspension of rats].
Reactive changes in right atrium cardiomyocytes during antiorthostatic tail suspension of rats commonly used to simulate low gravity have been studied by electron microscopy and morphometry. A 14 day suspension proved to increase contractile and secreting activities of cardiomyocytes. At the same time, signs of depleted activity are observed in some cells. Elongation of the experiment to 30 days leads to development of adaptive compensatory responses and increases their secreting capacity. A 30 day return to normal orthostatic position does not completely restores the structure and functioning of cardiomyocytes and leads to accumulation of internal secretion. A repeated 14 day suspension to a certain extent facilitates cardiomyocyte adaptation to altered conditions as compared to a single exposure; apparently, secretion release decreases while its production is activated.
Pogodina
L S
LS
Biological Faculty, Moscow State University, Vorob'evy gory, Moscow, 119992 Russia. lpogod@mail.ru
Shornikova
M V
MV
Chentsov
Iu S
IuS
D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D006325:Heart Atria / Q000166:cytology*; D019417:Hindlimb Suspension; D018472:Hypogravity; D008297:Male; D008854:Microscopy, Electron / Q000379:methods; D008929:Mitochondria, Heart / Q000502:physiology; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D018474:Weightlessness Simulation / Q000379:methods*