Rise In Na Concentration Research Articles

The relation between plasma Na concentration and salt gland Na?K ATPase content in the diamondback terrapin and the yellow-bellied sea snake

The Na−K ATPase activity of the diamondback terrapin (Malaclemys) lachrymal salt gland increased with a rise in Na concentration of the plasma. Considerable dehydration was necessary to obtain maximal stimulation of gland Na−K ATPase and some terrapins kept in sea water for many months may not have fully active glands. No changes occurred in lachrymal gland weight. The salt glands of salt injected or sea water acclimated terrapins (when plasma Na>200 mM), desert iguanas (Dipsosaurus) and sea snakes (Pelamis) contained comparable activities of Na−K ATPase. Sea snakes kept in fresh water for 48 days showed no decrease in salt gland Na−K ATPase activity or in gland weight, even though the plasma Na concentration diminished markedly.