snímek PPT
Fig. 7 Volume disorders correspond roughly to the hydratation derangements (with the exception of generalized edemas), as water penetrates easily all boundaries between the compartments. Tonicity is roughly the same in IC and EC space.
Paralelly with establishing these pathological conditions, transports of water (and electrolytes) take place between the IC a EC space: the differences of osmolality equalize quickly and buffering follows by means of electrolyte transports between IC and EC space – volume regulation effected by the cells
(Fig. 8a,b). It follows from these Fig. a.o. that the Na concentration in ECS (and in plasma) does not reflect the total Na content in the body.