Ex vivo and in vivo imaging of mouse parietal association cortex activity in episodes of cued fear memory formation and retrieval

Abstract

The parietal cortex in rodents has an integrative function and participates in sensory and spatial processing, movement planning and decision-making. However, much less is known about its functions in associative memory processing. Here using Fos immunohistochemical mapping of neuronal activity and two-photon imaging in Fos-eGFP mice we show an involvement of anterior part of the parietal cortex (PtA) in the formation and retrieval of recent fear memory in mice. Using ex vivo c-fos imaging we demonstrate the specific activation of the PtA during recent memory retrieval. In vivo two-photon c-fos imaging confirms these results as well as establishes the activation of the PtA neurons during fear memory formation. Additionally, we describe a design of Fos-Cre-GCaMP transgenic mice to investigate long-term changes of calcium dynamics in neurons captured with Fos-TRAP technique during fear conditioning training.

The Role of Perineuronal Nets in the Contralateral Hemisphere in the Electroacupuncture-Mediated Rehabilitation of Poststroke Dysphagia Mice

“…The similar result has been observed in the previous published study that changes in c-Fos were observed but no changes in neuronal activity were observed by in vivo electrophysiological recording (Yao et al, 2020). Although c-Fos, an intermediate early gene that serves as a molecular marker of neuronal activation (Ivashkina et al, 2021), it is expressed only in some kinds of neurons following peripheral stimulation, which might be inducible only in neurons that contain a particular neurotransmitter, that produce a particular kind of action potential, or that possess particular kinds of receptors. Therefore, it may be an incomplete marker for responsive activity (Bullitt, 1990).…”

Methodological comparison between fiber photometry and miniaturized endoscopes

“…An interesting technique to reduce this problem is the use of viral-based TRAP (targeted recombination in active populations) to express GCaMP only in the neurons which were naturally active during the task (Matos et al, 2019). Especially for miniscope studies, the utilization of Fos-Cre-GCaMP systems (Ivashkina et al, 2019) to assess longterm changes only in neurons that are related to a task holds a lot of promise for specifically associating shifts in neuronal activity to changes in behavior.…”

Top-down control and goal-directed behavior: on the role of the medial prefrontal cortex (mPFC) in positive and negative valence paradigms

“…The role of the mPFC is an instantiation of the importance of association cortices in the integration of information from lower hierarchical structures. It is possible that ensemble maturation in other association cortices, such as the parietal cortex (Ivashkina, Gruzdeva, Roshchina, Toropova, & Anokhin, 2019), or even in a cortex-wide dispersed-ensemble fashion (Roy et al, 2019).…”