A new efficient method for synaptic vesicle quantification reveals differences between medial prefrontal cortex perforated and nonperforated synapses
Date
2014Author
Nava, Nicoletta
Wegener, Gregers
Chen, Fenghua
Popoli, Maurizio
Randel Nyengaard, Jens
Metadata
Show full item recordAbstract
Communication between neurons is mediated by the
release of neurotransmitter-containing vesicles from
presynaptic terminals. Quantitative characterization of
synaptic vesicles can be highly valuable for understanding
mechanisms underlying synaptic function and plasticity.
We performed a quantitative ultrastructural
analysis of cortical excitatory synapses by mean of a
new, efficient method, as an alternative to threedimensional
(3D) reconstruction. Based on a hierarchical
sampling strategy and unequivocal identification of
the region of interest, serial sections from excitatory
synapses of medial prefrontal cortex (mPFC) of six
Sprague-Dawley rats were acquired with a transmission
electron microscope. Unbiased estimates of total 3D
volume of synaptic terminals were obtained through the
Cavalieri estimator, and adequate correction factors for
vesicle profile number estimation were applied for final
vesicle quantification. Our analysis was based on 79
excitatory synapses, nonperforated (NPSs) and perforated
(PSs) subtypes. We found that total number of
docked and reserve-pool vesicles in PSs significantly
exceeded that in NPSs (by, respectively, 77% and 78%).
These differences were found to be related to changes
in size between the two subtypes (active zone area by
86%; bouton volume by 105%) rather than to postsynaptic
density shape. Positive significant correlations were
found between number of docked and reserve-pool
vesicles, active zone area and docked vesicles, and
bouton volume and reserve pool vesicles. Our method
confirmed the large size of mPFC PSs and a linear correlation
between presynaptic features of typical hippocampal
synapses. Moreover, a greater number of
docked vesicles in PSs may promote a high synaptic
strength of these synapses
URI
http://hdl.handle.net/10394/16131https://onlinelibrary.wiley.com/doi/abs/10.1002/cne.23482
https://doi.org/10.1002/cne.23482
Collections
- Faculty of Health Sciences [2404]