[Influence of environmental salinity on the diffusion fluxes of water in the Isopod Sphaeroma serratum (Frabricius)].
1.--In Sphaeroma serratum, the diffusion fluxes of water are 3 or 4 times more important in sea water (SW) than in diluted (50%) sea water. In 100% and in 50% SW influx equals the outflux. 2.--When the animal is quickly transferred from 100% SW to 50% SW, and from 50% SW to 100% SW, the outflux is instantaneously and entirely reset. 3.--The main factor of the instantaneous resettlement of the outflux seems to be the variation of the concentration of Na+ or Cl- or both together in the external medium; the Ca2+ and Mg2+ concentrations do not seem to have any effect on the diffusion flux. 4.--The validity of our results is discussed (theory of unstirred layers, blood-circulation, oxygen interchange, ultrastructure). Our results are compared with those obtained in other Crustaceans and in Fishes.
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000494:pharmacology; D002712:Chlorides / Q000494:pharmacology; D003445:Crustacea / Q000502:physiology*; D004058:Diffusion; D008274:Magnesium / Q000494:pharmacology; D009994:Osmolar Concentration; D012623:Seawater; D012964:Sodium / Q000494:pharmacology; D014867:Water / Q000378:metabolism
D002712:Chlorides; D014867:Water; D012964:Sodium; D008274:Magnesium; D002118:Calcium
Etude des flux de diffusion de l'eau en fonction de la concentration du milieu extérieur chez l'isopode Sphaeroma serratum (Fabricius).