Northern blot of ganglionic distribution of enterin mRNA. A, Methylene blue-stained Northern blot of total RNA shows equal loading in all lanes. Aplysiaribosomal RNA runs as a single 18 sec band. B, Hybridization of the same blot with an enterin coding sequence cDNA probe. Kb, Kilobase; M, RNA size marker;B, buccal ganglion; C, cerebral ganglion;L, pleural ganglion; E, pedal ganglion;A, abdominal ganglion.