SPHK2 and stroke disorder: Hasegawa et al. (2013) examined the expression of the SphK and the S1P1 receptor in the ischemic area with a focus on neurons 6 h and 24 h after stroke by immunohistochemistry, and found a significantly decreased expression of S1P1, SphK1, and SphK2 starting at 6 h and significant at 24 h after MCAO.