Calcium image analysis in the moving gut.

Area of Science:

• Neuroscience
• Gastroenterology
• Microscopy

Background:

• Neural control of gastrointestinal muscle is poorly understood due to limitations in current calcium imaging techniques.
• Small-sample recordings are confounded by motion artifacts, paralytics, and tissue preparation.
• Existing methods struggle to capture accurate neural circuit activity in vivo.

Purpose of the Study:

• To develop and present resources for robust calcium imaging in moving gastrointestinal preparations.
• To enable accurate registration of images from dynamic samples.
• To identify and correct for out-of-focus events in widefield fluorescent microscopy.

Main Methods:

• Piecewise rigid registration with pathfinding to correct for smooth muscle contractions.
• Novel methods for identifying and mitigating loss-of-focus events.
• Simulation of calcium activity to validate registration accuracy.

Main Results:

• Developed an image analysis pipeline capable of capturing concurrent calcium dynamics from larger neuronal populations and fields of view.
• Identified distinct neuronal population activity patterns in response to stimuli, aligning with hypothesized functions.
• Source code for algorithms is publicly available, alongside recommendations for improving calcium imaging data quality.

Conclusions:

• The developed methods facilitate large-population, high-quality calcium imaging recordings in the gut.
• Enables more sophisticated network analyses of neural activity.
• Provides deeper insights into the complex neural patterns governing gastrointestinal function.