Evidence for the involvement of the Na+-K+-ATPase in the mechanism of axonal protein and nucleoside transport.

[3H]Proline and [3H]uridine were injected into both eyes of the goldfish. 1 h before and after this injection 3X10)-6)M ouabain was administrated unilaterally to the retina. 8 h and 24 h after tracer injection the radioactivity in the retina, optic nerve and tectum was measured. It is suggested that the inhibition of the neuronal Na+-K+-ATPase inside the retina is responsible for the reduction of the labelled material transported into the optic nerve.