Chemical analysis of neurotransmitter candidates in clonal cell lines from Drosophila central nervous system, II: Neuropeptides and amino acids.

In a previous study, we have found acetylcholine and/or L-DOPA in 10 colonial clones from one cell line of Drosophila larval central nervous system (CNS). In this study, to characterize clonal neuronal phenotypes further, we have examined three neuropeptides and 19 amino acids using HPLC system. Substance P and proctolin were found in seven and eight out of ten clones, respectively. On the other hand, somatostatin was expressed in all ten clones. GABA and taurine were not detected in any clones. Glutamate, which is an excitatory transmitter in Drosophila, was found in all the clones, although its content was different seven times among them. Glycine, which is not known as a transmitter in Drosophila, was found to be unevenly expressed among them. Therefore, the conspicuous expression of peptides or amino acids in some clones suggests that the substances have a special role in Drosophila CNS.