Cysteinyl leukotriene receptor 1 partially mediates brain cryoinjury in mice

Aim:To determine whether the cysteinyl leukotriene receptor 1(CysLT1receptor)modulates brain cryoinjury and whether the CysLT1receptor antagonist pranlukastexerts a time-dependent protective effect on cryoinjury in mice.Methods:Braincryoinjury was induced by applying a liquid nitrogen-cooled metal probe to thesurface of the skull for 30 s.Brain lesion,neuron density,and endogenous IgGexudation were observed 24 h after cryoinjury.Transcription and the expressionof the CysLT1receptor were detected by RT-PCR and immunoblotting,and thelocalization of the receptor protein by double immunofluorescence.Results:ThemRNA and protein expressions of the CysLT1receptor were upregulated in thebrain 6-24 h after cryoinjury,and the CysLT1receptor protein was primarily local-ized in the neurons,not in the astrocytes or microglia.Pre-injury treatments withmulti-doses and a single dose of pranlukast (0.1 mg/kg) attenuated cryoinjury;postinjury single dose (0.1 mg/kg) at 30 min (not 1 h) after cryoinjury was alsoeffective.Conclusion:The CysLT1receptor modulates cryoinjury in mice at leastpartly,and postinjury treatment with its antagonist pranlukast exerts the protec-tive effect with a therapeutic window of 30 min.