An electrophysiological, pharmacological and fluorescent study on twelve identified neurones from the brain of Helix aspersa

Abstract

1. 1. Six large cells in the right parietal and six large cells in the visceral ganglia of Helix aspersa have been identified using electrophysiological techniques. 2. 2. Fluorescence studies on these cells have shown that in the right parietal ganglion three out of the six cells studied contained 5-hydroxytryptamine (5-HT) in their cytoplasm. 3. 3. In the visceral ganglion five out of the six cells examined contained 5-HT. None of these cells contained a catecholamine. 4. 4. The 5-HT containing cells in both ganglia had a similar pharmacology. These cells were depolarized by acetylcholine and 5-HT and hyperpolarized by dopamine. 5. 5. The nerve inputs of the cell in the right parietal ganglion were all ILD type responses. In contrast most of the responses to nerve stimulation in the visceral cells were of an EPSP type.