TLR4 and Intraventricular hemorrhage: In inflammatory conditions, a modelled in rats with intraventricular hemorrhage, hypersecretion of CSF was reported to be mediated by TLR4-dependent activation of the Ste20-type stress kinase SPAK, which binds, phosphorylates, and stimulates the NKCC1 at the choroid plexus epithelium apical membrane [83].