The objective of the present study is to investigate the effect of a stroke mimic condition on human brain pericytes. Comparative gene expression analysis was performed using cultured human brain microvascular pericytes with 1% oxygen for 24 hours or with acidic condition at pH 6.5 for 24 hours. Gene expression was analyzed using 3D-Gene® Human 25k oligonucleotide microarrays and computational gene expression analysis tools. Incubation of cells under these conditions resulted in significant changes in numerous genes related with glycolysis, immune responses, and angiogenesis. Overall design: Two-condition experiment, control vs. hypoxia or control vs. acidic condition. Biological replicates: 2 control vs. hypoxia, 2 control vs. acidic condition, independently grown and harvested. Cells were exposed for 24 hours to hypoxia (1%O2, 5% CO2, humidified atmosphere) or acidic medium (pH 6.5). Control cells were kept at pH 7.4, in 20% O2, 5% CO2, humidified atmosphere.