1. Literature Review 1

2. Background Keywords:  PKMζ protein kinase M zeta, constitutively active form of an atypical protein kinase C (PKC) isozyme  ZIP the PKMζ inhibitor zeta pseudosubstrate inhibitory peptide SCR ZIP scrambled ZIP 2

3. Method:  Subject: male SD Rats  Induction fear memory Startle evoked by 50ms 95dB white noise Conditioned stimulus 4s exposure odorant(acetophenone) Unconditioned stimulus 0.5s 0.4mA foot shock  In 3

4. Method: Five parings of the ordrant and foot shock Rats were sorted into different groups based on the baseline Testing retention of memory at various intervals after injection treatments. 4

5. Results: Histological confirmation drug injection site is in amygdala The memory could be disrupted 2h after the injection of ZIP 5

6. Results: ZIP infusion caused a significant disruption (P < 0.05, t test) of fear memory when tested 2 d after infusion (left), but not in rats tested 15 d after infusion 6

7. Results: PKMζ blockade in the amygdala only disrupts memory at long retention intervals if rats are tested shortly after infusion. 7

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10. Conclusion:  The expression of fear memory was disrupted when the inhibitor was applied shortly before testing, it had no effect when rats were tested with longer retention intervals. These results suggest that PKMz inhibition does not erase memory, but temporarily disrupts expression of memory. 10