Phospholipase A2 inhibition in the rat hippocampus disrupts short- and long-term memory processing

In early Alzheimer’s disease (AD) there is an impairment of episodic short-term (STM) and long-term memory (LTM). Decreased phospholipase A₂ (PLA₂) activity has been reported in the hippocampus of AD brains. In rat hippocampal slices, PLA₂ has been implicated in mechanisms of synaptic plasticity involved in memory formation. Adult Wistar rats were bilaterally implanted with indwelling cannulae in the CA1 region of the dorsal hippocampus. After surgery, animals were submitted to one session of step-down inhibitory avoidance training. Animals received a bilateral infusion of a vehicle or of the PLA2 inhibitor MAFP given 30min before training. The animals were tested for STM and LTM after training. Infusion of MAFP impaired both STM and LTM processing of the inhibitory avoidance. These findings suggest that reduced PLA₂ activity may contribute to the memory impairment in AD.