Spatio-temporal expression of cysteinyl leukotriene receptor-2 mRNA in rat brain after focal cerebral ischemia

Cysteinyl leukotrienes (CysLTs) induce inflammatory responses mediated by activating CysLT1 and CysLT2 receptors. We have recently reported that CysLT1 receptor expression is increased in rat brain after focal cerebral ischemia and the increased expression is spatio-temporally related to acute neuronal injury and late astrocyte proliferation. Here we report spatio-temporal expression of CysLT2 receptor mRNA in rat brain after focal cerebral ischemia induced by 30 min of middle cerebral artery occlusion. We found that the neuron density was gradually decreased or disappeared in the ischemic core and boundary zone during 14 days after reperfusion, and the astrocyte population in the boundary zone was increased 3–14 days after reperfusion. In the ischemic core, the expression of CysLT2 receptor mRNA was increased at 6, 12 and 24 h and then recovered at 3, 7 and 14 days after reperfusion. In the boundary zone, the expression was significantly increased 3, 7 and 14 days after reperfusion. The results suggest that CysLT2 receptor may be related to the acute neuronal injury and late astrocyte proliferation in the ischemic brain.