A neuronal network from the mollusc Lymnaea stagnalis

Area of Science:

• Neuroscience
• Invertebrate Neurobiology
• Computational Neuroscience

Background:

• The central nervous system (CNS) of Lymnaea stagnalis contains identified neurons involved in vital behaviors.
• Specific neuronal networks controlling locomotion and cardio-respiratory functions require detailed characterization.
• Understanding electrical coupling and synaptic interactions is crucial for deciphering neural circuit function.

Purpose of the Study:

• To investigate the morphology, electrophysiology, and synaptic inputs of a specific ventral neuronal network in Lymnaea stagnalis.
• To characterize the electrical coupling and activity patterns of neurons RPV1, RPV2, and RPV3.
• To identify the modulatory inputs from other interneurons (visceral dorsal four, Input three, RPeD11) onto this network.

Main Methods:

• Electrophysiological recordings (in vivo and in vitro) to assess neuronal activity and coupling.
• Lucifer yellow staining for morphological characterization and tracing axonal projections.
• In vitro co-culture experiments to study synapse formation between identified neurons.

Main Results:

• Three neurons (RPV1, RPV2, RPV3) were found to be electrically coupled, with varying strengths (RPV2&3 strong, RPV1&2/RPV1&3 weak).
• RPV1 exhibited bursting activity, while RPV2 and RPV3 showed tonic firing or silence.
• RPV1-3 received inhibitory inputs from visceral dorsal four and Input three, and excitatory input from RPeD11, influencing locomotion and cardio-respiratory functions.

Conclusions:

• The RPV1-3 neuronal network plays a role in locomotion and cardio-respiratory control in Lymnaea stagnalis.
• Electrical coupling and specific synaptic inputs shape the network's activity patterns.
• This preparation serves as a valuable model for studying synapse formation and bursting activity in vitro.