Transient Excitation before Fear Conditioning- Abaza


I found the second paper (2014) very impressive in its ability to induce excitation, by multiple measures, including, Transfecting HSV-CREB viral vector, Double Knockout of a K+ re-polarization channel, and finally CHR2 opto-genetic transgenic activation. What I found very interesting was that the enhanced fear memory formation effect by CREB persisted even 14 days after training showing that this ubiquitous binding protein mediates long term processes. This is not surprising as research into cAMP mediated CRE activation induces LTP and long term memory consolidation. It is thus reasonable to parallel this effect happening for fear memory formations in the Lateral Amygdala. Ablation of CREB neurons activated during fear memory, induced amnesia and not only the deletion of a single context specific memory. This was discussed and posited to be potentially involved in a broader neural network of memory encoding. Finally, I should also address that since the OFT and ELPM behavioral assays did not show significant differences across groups, it is interesting to note that LA neuronal CREB mediated fear memory acquisition is limited to fear and not anxiety. When thinking about pathologies such as PTSD, it would be of value to determine the extent to which fear memories and the amygdala are involved. Perhaps since neuronal excitation primes fear memory acquisition, instead of ablating neurons, we could target excitable neurons in the LA of clinical patients and reduce their excitability by perhaps modulating K+ channels. This sort of clinical work would need more research on the effects of selective neuronal ion channel targeting via in vivo viral transfection, or CRISPR edited IPS/neuroblast transplantation.

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