Localization of axonally transported [3H]glycine in vesicles of identified neurons.

A specific association of axonally transported, free [3H]glycine with vesicles in the identified neurons R3-R15 of Aplysia is demonstrated by high resolution autoradiography. The association of glycine with vesicles, the first such finding in any animal for a neuroactive amino acid, adds to evidence that glycine may be utilized as a neuro-chemical messenger by R3-R14.