ZIP (Zeta inhibitory peptide) is a specific inhibitor of protein kinase Mζ (PKMζ), which plays a key role in the maintenance of long-term potentiation (LTP) and memory processes. While ZIP is effective in blocking synaptic potentiation and has been extensively used to explore various memory-related tasks in rodents, research shows that its inhibitory effects on LTP and long-term memory (LTM) are independent of the presence of PKMζ, as evidenced by findings in knock-out mice. This raises the possibility that ZIP may exert its effects through alternative mechanisms, potentially involving ionotropic glutamate AMPA receptors (AMPARs).
