Microfluidic local perfusion chambers for the visualization and manipulation of synapses

Area of Science:

• Neuroscience
• Cell Biology
• Biotechnology

Background:

• Synaptic function is complex due to neuron polarization and synapse structure.
• Existing methods struggle with precise manipulation and visualization of synaptic processes.

Purpose of the Study:

• To develop a novel microfluidic device for controlled manipulation of synaptic regions.
• To investigate synapse-to-nucleus signaling pathways in vitro.
• To analyze the impact of glutamate application patterns on neuronal responses.

Main Methods:

• Development of a microfluidic local perfusion (microLP) chamber.
• Culturing of parallel neuron rows for synapse formation.
• High-resolution perfusion for localized chemical application.
• Calcium imaging using Fluo-4 NW.
• Analysis of phosphorylated CREB (pCREB) and Arc transcript levels.

Main Results:

• The microLP chamber successfully facilitated synapse formation and manipulation.
• Local glutamate perfusion induced measurable calcium changes in dendrites and somata.
• Spaced vs. massed glutamate application differentially affected pCREB levels.
• DHPG application led to increased Arc transcription and localization.

Conclusions:

• The microLP chamber provides unprecedented spatial and temporal control for studying synaptic biology.
• This technology enables detailed investigation of synapse-to-nucleus communication.
• The findings highlight the differential impact of stimulation patterns on neuronal signaling pathways.