Multiple intrinsic membrane properties are modulated in a switch from single- to dual-network activity

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• Neural network flexibility allows neurons to switch between single- and dual-network activity.
• Previous work identified a neuron switching networks via intrinsic property modulation, but specific properties were unknown.

Purpose of the Study:

• To investigate the intrinsic property modulation underlying neuropeptide-elicited neuronal switching in the Jonah crab stomatogastric nervous system (STNS).
• To identify candidate ion channels contributing to Gly 1 -SIFamide-induced intrinsic bursting in the lateral posterior gastric (LPG) neuron.

Main Methods:

• Used small networks in the Jonah crab (Cancer borealis) STNS.
• Isolated the LPG neuron using pharmacology and hyperpolarizing current injection.
• Applied ion substitution and channel blockers to identify contributing ion currents.

Main Results:

• Gly 1 -SIFamide increased LPG intrinsic excitability, rebound from inhibition, and decreased spike frequency adaptation, promoting intrinsic bursting.
• Hyperpolarization-activated current, persistent sodium current, and calcium currents were identified as primary contributors to LPG intrinsic bursting.
• Intrinsic bursting was more sensitive to current blockers when LPG received rhythmic electrical input from the fast network compared to isolation.

Conclusions:

• Switching from single- to dual-network activity involves modulation of multiple intrinsic neuronal properties.
• Synaptic input from a second network can modulate the contribution of these intrinsic properties.
• Identified key ion channels underlying neuropeptide-induced intrinsic bursting and neuronal network switching.