Platelet-activating factor receptor is not required for longterm potentiation in the hippocampal CA1 region

From pharmacological studies, platelet-activating factor (PAF) has been pro posed as a retrograde messenger for long-term potentiation (LTP) in the hip pocampal CA1 region. We re-examined a possible contribution of PAF to LTP w ith a more specific approach using mice deficient in the PAF receptor. The PAF receptor-deficient mice exhibited normal LTP and showed no obvious abno rmality in excitatory synaptic transmission. We also performed pharmacologi cal experiments on the wild-type mice. Two structurally different antagonis ts of PAF receptors had no effects on LTP, Furthermore, the application of PAF itself caused no detectable changes in excitatory synaptic transmission . Thus, we conclude that the PAF receptor is not required for LTP in the CA 1 region.