Frequent spontaneous seizures followed by spatial working memory/anxiety deficits in mice lacking sphingosine 1-phosphate receptor 2

► S1P2−/− mice manifested severe and frequent spontaneous seizures on a C57BL/6N background. ► Forty percent of S1P2−/− mice died after seizures while the remaining 60% survived. ► Enhanced gliosis was observed in the neocortex/hippocampus of surviving S1P2−/− mice. ► Nearly half of the deliveries from pregnant S1P2−/− mice resulted in neonatal death. ► Adult S1P2−/− mice displayed impaired spatial working memory and increased anxiety.