Metabolic and hormonal mechanisms of mineral metabolic adaptation to induced hypokinetics in rats
Saiki, H.; Nakaya, M.; Sugita, Y.; Kamachi, M.
Aviation Space and Environmental Medicine 47(8): 846-852
1976
ISSN/ISBN: 0095-6562 PMID: 949304 Document Number: 100956
During simulated hypokinetics, many biological functions have a tendency to stabilize at different levels with the passing of time. In this experiment, hypokinetic exposure was induced in albino rats by the suspension method for 5 weeks. A new plateau in urinary K+ excretion was attained during the third week, after a transient decrease during the first week. Since the formation of this steady plateau is considered a manifestation of the adaptation of this function, the hypokinetic exposure period was divided into a prestabilized phase and a stabilized phase. To ascertain the biochemical mechanisms of this adaptation process, the effects of aldosterone and anti-aldosterone substances (e.g., tetracycline) on K+ and Na+ excretion patterns in each phase were investigated. Decreasing aldosterone activity in the prestabilized phase and increasing activity in the stabilized phase are recognized as one of the main factors in the renal adaptation process to hypokinetics.