S1PR1 and Grade I preterm intraventricular hemorrhage: Selective S1P1 drugs may be more powerful against brain hemorrhage than fingolimod given that it provided conflicting results, i.e. fingolimod failed to show protective effects after experimental intracerebral hemorrhage in one of the studies34, whereas protective effects were reported in an another study in mice35 and in a model of germinal matrix hemorrhage in rat pups36.