| The neurotransmitters gamma aminobutyric acid (GABA) and nitric oxide (NO) play a role in maintaining the larval state in the eastern mud snail, Nassarius obsoletus, but how GABAergic and nitrergic neurons are organized in the neural circuit that controls metamorphosis is unknown. Because of previous work by other members of my laboratory, I hypothesized that GABAergic neurons would be upstream from the nitrergic ones. Larval N. obsoletus were exposed to various combinations of GABAergic and nitrergic compounds in bath application and the resulting numbers of metamorphosed individuals were counted after 24 and 48 hours.. I performed multiple sets of experiments and while some indicated that GABAergic neurons were upstream from nitrergic ones the data as a whole did not reveal a clear organizational scheme to this pathway, so I suggest instead that GABA and NO may function in separate pathways to influence the onset of metamorphosis. |
