Régulation osmotique intracellulaire chez Asterias Rubens L., rôle du glycocolle et de la taurine

The mechanism of euryhalinity in Asterias rubens has been studied in a batch collected in the Channel (Coast of Brittany). These starfishes are able to survive for at least a period of 10 days in a medium containing 60% sea water (A:-1°23C), when the transfer from sea water is realized progressively, within three days. During the adaptation to dilluted sea water, the osmotic pressure of the internal medium (perivisceral fluids) is the same as that of the external medium. The tissues of the gastric caeca, however, shows only a small variation of hydration, which implies an effective isosmotic intracellular regulation. The variation in the intracellular concentration of the free glycine and the free taurine in the tissues, plays an important part in this mechanism.