Abstract: Objective To explore the effect of blood-brain barrier disruption on expression of AQP-4, through comparing the cell morphology and the expression of aquaporin-4 (AQP-4) of cultured astrocytes in medium with and without fetal bovine serum (FBS).Methods Cerebral cortical astrocytes from female Wistar rats were cultured in serum free medium, DMEM supplemented with 10% FBS, and serum free medium supplemented with 10% FBS. Phase contrast microscope was used to detect the cell morphology and cell size. Immunofluorescence staining and reverse real-time quantitative polymerase chain reaction (RT-qPCR) were used to examine the expression of glial fibrillary acidic protein (GFAP), AQP-4 and metabotropic glutamate receptor 5 (mGluR5).Results Astrocytes in serum free medium showed extensive process bearing morphology, small body and nucleus, and high refractivity. In contrast, in two kinds of 10% FBS-containing medium, astrocytes were flat with large body and nucleus, weak refractivity, as well as short process. Analysis of immunofluorescence staining and RT-qPCR revealed a down-regulation of GFAP and AQP-4 protein and mRNA expression in two kinds of 10% FBS-containing medium, compared with that in serum free medium (P<0.001), however, there was no difference in mGluR5 protein and mRNA expression (P>0.05). Conclusion FBS changed astrocyte morphology and down-regulated the expression of GFAP and AQP-4.

Key words: astrocytes, serum, aquaporin-4, glial fibrillary acidic protein, metabotropic glutamate receptor subtype 5, rats