Distribution of sensorin immunoreactivity in the central nervous system of Helix pomatia: functional aspects.
Land snails belonging to the genus Helix are commonly used to study several behaviors and their plasticity at the cellular level. Because the knowledge of sensory neurons in these species is far from being complete, we have investigated the presence and distribution in Helix pomatia central nervous system of the immunoreactivity for sensorin, a peptide specific for mechanosensory neurons in Aplysia. We found that the majority of immunopositive cells were grouped in clusters located in all the central ganglia, except for the pedal ganglion, where only a single large neuron was stained. A symmetrical cluster of stained cells in the cerebral ganglia showed homology with the cerebral J clusters in Aplysia. Most of the somata of these Helix cerebral clusters send their axons in the ipsilateral cerebropedal connective and lip nerves and make monosynaptic connections with cells located in a medial adjacent cluster. This monosynaptic circuit can be reestablished in culture, where it shows homosynaptic depression as it does in the ganglionic preparation.
Casadio
Andrea
A
Dipartimento di Neuroscienze, Sezione di Fisiologia, Universitá di Torino, Torino, Italy.
Fiumara
Ferdinando
F
Sonetti
Dario
D
Montarolo
Pier Giorgio
PG
Ghirardi
Mirella
M
D000818:Animals; D002478:Cells, Cultured; D002490:Central Nervous System / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D004558:Electric Stimulation; D004594:Electrophysiology; D019706:Excitatory Postsynaptic Potentials / Q000528:radiation effects; D005456:Fluorescent Dyes / Q000378:metabolism; D017952:Ganglia, Invertebrate / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D006372:Helix, Snails; D007150:Immunohistochemistry; D009474:Neurons / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D009479:Neuropeptides / Q000378:metabolism*; D013569:Synapses / Q000502:physiology / Q000528:radiation effects; D014018:Tissue Distribution
D005456:Fluorescent Dyes; D009479:Neuropeptides