[Calcium pooling by plasma and extra-plasma buffer systems: effects of prolonged hypokinesia].
Healthy test subjects were intravenously injected with calcium solutions during ambulatory activity and after 100-day exposure to head-down tilt. It was demonstrated that different mechanisms were involved in maintaining ionized calcium at a constant level and that their contribution changed after the tilt study. It was also shown that the capacity of extra plasma pool was decreased, kinetic characteristics of the Ca2+ binding reaction were modified, and responses of mineralotropic hormones to induced hypercalcemia were enhanced.
Larina
I M
IM
Smirnova
T M
TM
Sukhanov
Iu V
IuV
D000293:Adolescent; D000328:Adult; D002021:Buffers; D002118:Calcium / Q000097:blood / Q000378:metabolism*; D018475:Head-Down Tilt; D006706:Homeostasis; D006801:Humans; D006934:Hypercalcemia / Q000209:etiology*; D018476:Hypokinesia / Q000378:metabolism*; D008297:Male; D013026:Space Flight; D013997:Time Factors; D014893:Weightlessness
D002021:Buffers; D002118:Calcium
Reaktsiia srochnogo deponirovaniia kal'tsiia plazmennymi i vneplazmennymi bufernymi sistemami: vliianie usloviĭ dlitel'noĭ gipokinezii.