Worm Breeder's Gazette 8(3): 46
These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.
Using anti-GABA antisera, we have identified possible GABAnergic neurons in C. elegans. The ventral and dorsal nerve cords, a series of commissures, and a number of cell bodies of the ventral nervous system stain with this antibody. Swellings are often visible along the commissures near the region of the sublateral nerve cords, suggesting that synapses might be present. The number and locations of these cells and processes indicate that they may be the DD and VD motorneurons. These neurons correspond anatomically to the D1 and V1 motorneurons of Ascaris, which Johnson et al. have shown to have GABA- like immunoreactivity (Newsletter, Vol. 8 No. 2). We have also observed staining in both the heads and tails of C. elegans hermaphrodites and males. The most striking staining in the head is a set of four neurons immediately anterior to the nerve ring; we have tentatively assigned these cells to be the RME neurons. (Four cells resembling the RME neurons of C. elegans have been found by Johnson et al. to be GABA-positive in Ascaris.) The head neurons posterior to the nerve ring and the neurons in the tail remain to be identified. In our staining protocol, animals were fixed overnight in 4% paraformaldehyde/1% glutaraldehyde and then permeablized by sequential treatment with elastase and collagenase. (This technique allows adequate antibody penetration through the cuticle for wholemount staining.) Animals were then incubated first with a rabbit-anti-GABA primary antiserum, second with a goat-anti-rabbit IgG secondary antiserum, and third with a peroxidase-(rabbit) anti-peroxidase complex (PAP technique). The chromogen diaminobenzidine then served as the substrate for the peroxidase and produced a colored reaction product allowing localization of cross-reactive substances. We have also found that a fluorescent secondary antibody gives similar results.