Rationale: Authors examined the distribution of STAT3 in the rat brain. Using western blotting and subcellular fractionation authors found STAT3 immunoreactivity in the various subcellular fractions, including synaptic fractions. Then, they performed electron microscopy in the cerebral cortex with DAB enhancement, with and without post-staining to enhance visualization of some structures. By doing this, authors found PSDs and subsynaptic regions strongly labelled, though non-immunoreactive PSDs were also observed. Presynaptic terminals were not labelled. Moreover, authors also found phosphorylation of STAT3 in PSD fractions, which suggest that STAT3 signaling occurs at postsynaptic sites.. Experimental description: From M&M:
Postsynaptic density (PSD) fractions of the forebrain were obtained from Wistar rats.
For immunohistochemical examination at the light microscopic level, brains from Wistar rats were used.