Brain circuits are highly interconnected three-dimensional structures fabricated from components ranging vastly in size; from cell bodies to individual synapses. While neuronal activity can be visualized with advanced light microscopy (LM) techniques, the resolution of electron microscopy (EM) is critical for identifying synaptic connections between neurons. Here, we combine these two techniques, affording the advantage of each and allowing for measurements to be made of the same neural features across imaging platforms. We established an EM-label-free workflow utilizing inherent structural features to correlate in vivo two-photon LM and volumetric scanning EM (SEM) in the ferret visual cortex. By optimizing the volume SEM sample preparation protocol, imaging with the OnPoint detector, and utilizing the focal charge compensation device during serial block-face imaging, we achieved sufficient resolution and signal-to-noise ratio to analyze synaptic ultrastructure for hundreds of synapses within sample volumes. Our novel workflow provides a reliable method for quantitatively characterizing synaptic ultrastructure in functionally imaged neurons, providing new insights into neuronal circuit organization.
You may also like
Mapping unknown territory
February 27, 2023Max Planck Institute for Biological Intelligence
Modeling the turtle brain provides insights: Routing...
February 15, 2023Max Planck Institute for Brain Research
Amygdala Intercalated Cells: Gatekeepers and Conveyors...
January 19, 2023Max Planck Florida Institute for Neuroscience
Aversive bimodal associations differently impact...
January 19, 2023Max Planck Institute for Chemical Ecology
In the zone for memories
January 10, 2023Max Planck Institute for Brain Research
Commonalities and Asymmetries in the Neurobiological...
January 5, 2023Max Planck Institute for Psycholinguistics