To test this hypothesis and specifically elucidate the role of CysLT1R during AD pathogenesis, we downregulated the expression levels of CysLT1R by knockout or knockdown of the CysLT1R gene in APP/PS1 mice for the first time, and examined the effects of CysLT1R manipulation on amyloidosis, synaptic plasticity, cognition, neuroinflammation, and KP regulation. Here, APP is linked to Alzheimer disease.