Exchange of phospholipid-bound Na in the toad bladder with 24Na.

TLDR: Using 24Na it is evident that the bound sodium can be more readily labeled with 24Na from the mucosal side of the bladder, than with 24 Na from the serosal side, which supports the theory that the phospholipids play an important role in active sodium transport.

Abstract: Summary The phospholipids of the toad bladder bind sodium. Using 24Na it is evident that the bound sodium can be more readily labeled with 24Na from the mucosal side of the bladder, than with 24Na from the serosal side. This observation supports the theory that the phospholipids play an important role in active sodium transport.