We investigated the effect of elevated levels of humoral 5HT and DA on the feeding latency of Helix pomatia, 1 day, 3 days and 10 days following satiation, by injecting monoamines into the haemocoel. HPLC assay of monoamines showed that both 5HT and DA are present in pmol/ml concentrations in the haemolymph of both starved and non-starved animals. Elevated levels of 5HT and DA were most effective at decreasing the feeding latency 10 days following satiation when DA decreased the feeding latency in a concentration dependent manner between 10−7 and 10−5 M whereas 5HT levels decreased the feeding latency only at 10−6 M but increased it at 10−5 M. Immunocytochemistry revealed that both 5HT3 and D1 receptor-like immuno-reactivity are present in cell bodies located in the same areas of the buccal ganglia. Our observations suggest that both humoral DA and 5HT mutually modulate the activity of the feeding CPG through neurons which have these receptors.
Alex, K. D., Pehek, E. A. (2006) Pharmacological mechanisms of serotonergic regulation of dopamine neurotransmission. Pharmacol. Therapeutic. 113, 296–320.
Chase, R. (2002) Behavior and its neural control in gastropod mollusks. Oxford University Press, Oxford–New York.
Dickinson, P. S. (2006) Neuromodulation of central pattern generators in invertebrates and vertebrates. Curr. Opinion. in Neurobiol. 16, 604–614.
Elliott, C. J. H., Susswein, A. J. (2002) Comparative neuroethology of feeding control in molluscs. J. Exp. Biol. 205, 877–896.
Faerber, L., Drechsler, S., Ladenburger, S., Gschaidmeier, H., Fischer W. (2007) The neural 5-HT3 receptor network after 20 years of research-Evolving concepts in management of pain and inflammation. E. J. Pharmacol. 560, 1–8.
Gerhardt, C. C., Heerikhuizen, H. (1997) Functional characteristics of heterologously expressed 5-HT receptors. E. J. Pharmacol. 334, 1–23.
Hernádi, L., Vehovszky, Á., Győri, J., Hiripi, L. (2007) Neuronal background of activation of aestivated snails, with special attention to the monoaminergic system: a biochemical, physiological, and neuroanatomical study. Cell Tiss. Res. 331, 539–553.
Hernádi, L., Vehovszky, Á., Hiripi, L., Győri, J., Walker, R. J., Elekes, K. (2005) Neuroanatomical, immunocytochemical, and physiological studies of the pharyngeal retractor muscle and its putative regulatory neurons playing role in withdrawal and feeding in the snail, Helix pomatia. Cell Tiss. Res. 321, 257–271.
Kabotyanski, E. A., Baxter, D. A., Cushman, S. J., Byrne, J. H. (2000) Modulation of fictive feeding by dopamine and serotonin in Aplysia. J. Neurophysiol. 83, 374–392.
Levenson, J., Byrne, J. H., Eskin, A. (1999) Levels of serotonin in the hemolymph of Aplysia are modulated by light/dark cycles and sensitization training. J. Neurosci. 19, 8094–8103.
Murphy, A. D. (2001) The neuronal basis of feeding in the snail Helisoma, with comparison to selected gastropods. Prog. Neurobiol. 63, 383–408.
Neve, K. A., Seamans, J. K., Trantham-Davidson, H. (2004) Dopamine receptor signaling. J. Receptors and Signal Transductio. 24, 165–205.
Peschel, M., Straub, V., Teyke, T. (1996) Consequences of food-attraction conditioning in Helix: a behavioral and electrophysiological study. J. Comp. Physiol. A. 178, 317–327.
Spier, A., Wotherspoon, G., Nayak, S., Nicolson, R., Priestly, J., Lummis, S. (1999) Antibodies against the extracellular domain of the 5-HT3 receptor label both native and recombinant receptors. Brain Res. Mol. Brain Res. 67, 221–230.
Walker, R. J., Brooks, H. L., Holden-Dye, L. (1996) Evolution and overview of classical transmitter molecules and their receptors. Parasitology 113, Suppl. S3–33.
Werkman, T. R., De Vlieger, T. A., Stoof, J. C. (1990) Indications for a hormonal function of dopamine in the central nervous system of the snail Lymnaea stagnalis. Neurosci. Lett. 108, 167–172.
Yeoman, M. S., Brierley, M. J., Benjamin, P. R. (1996) Central pattern generating interneurons are targets for the modulatory serotonergic cerebral giant cells in the feeding system of Lymnaea. J. Neurophysiol. 75, 11–25.
About this article
Cite this article
Hernádi, L., Kárpáti, L., Győri, J. et al. Humoral Serotonin and Dopamine Modulate the Feeding in The Snail, Helix pomatia. BIOLOGIA FUTURA 59, 39–46 (2008). https://doi.org/10.1556/ABiol.59.2008.Suppl.6
- D1 receptor-motivation
- 5HT3 receptor
- feeding latency