Core Concepts
A deep learning-based computational pipeline enables automated reconstruction and quantification of geometric changes across the cerebral microvascular network in response to optogenetic stimulation of nearby neurons.
Abstract
The content describes the development and application of a deep learning-based computational pipeline for analyzing two-photon fluorescence microscopy (2PFM) data of the cerebral microvascular network in optogenetically-modified mice.
Key highlights:
- The pipeline enables automated segmentation, registration, and graph-based analysis of the microvascular network from 4D 2PFM data.
- It was applied to study neurovascular coupling in Thy1-ChR2-YFP mice, where optogenetic stimulation of pyramidal neurons was used to elicit vascular responses.
- Analysis revealed heterogeneous changes in vessel caliber along individual vessels, with both dilations and constrictions observed.
- Vessels farther from activated neurons tended to constrict, while those closer dilated.
- Vascular responses showed increased coordination (assortativity) with higher stimulation intensities.
- The highest stimulation intensity led to a 4% increase in the efficiency of the capillary network.
- The pipeline enables detailed mapping of neurovascular coupling at the network level, going beyond previous studies focused on individual vessels or tissue-level responses.
Stats
Vascular segments exhibited an average radius change of 24 ± 28% of the resting diameter within individual vessels.
Dilations occurred 16.1±14.3 μm away from the closest neuron, while constrictions occurred 21.9±14.6 μm away.
The assortativity of vascular radius changes increased by 152 ± 65% at 4.3 mW/mm2 blue light stimulation compared to baseline.
The median efficiency of the capillary network increased by 4% during 4.3 mW/mm2 blue light stimulation compared to control.
Quotes
"Neuronal function impairments arise wherever local metabolite supply becomes inadequate, notwithstanding the physiological level of flow across the network as a whole, making mapping of vessel changes across the network of particular importance."
"Vessels farther from activated neurons tended to constrict, while those closer dilated."
"Only the highest photostimulation intensity elicited an increase in the network efficiency."