SLCO3A1 and cholestasis: Oatp3a1 was previously quantified in theporcine choroid plexus, brain capillary, and retinal pigment epithelium.34 With its multiple isoforms, the location ofOatp3a1 can vary from basolateral to apical expression.56,57 The cell-specific location in CE is still unknown, but in the choroidplexus, OATP3A1_v1 was located to the basolateral side and OATP3A1_V2and _V3 to the apical side.56,57 Its physiological roleis still unknown, but in a study by Pan et al.,58 OATP3A1 was upregulated as a response to cholestasis inthe liver.