Effect of wood block enrichment on gene expression data in rat liver and spleen following treatment with cyclophosphamide for 5 days

Wood blocks are a suggested form of rodent enrichment, however, if ingested, wood blocks could potentially confound early toxicology results. We used microarrays to determine if transcriptomically, rats treated with cyclophosphamide and administered wood blocks were different from those treated with cyclophosphamide and not allowed access to wood blocks Rats (n=3/group) were dosed orally with 40 mg/kg/day Cyclophosphamide or vehicle. In each group half of the rats were allowed access to wood blocks and the other half were not allowed access to wood blocks. At necropsy the liver and spleen were removed and flash frozen in liquid nitrogen. The frozen organs were homogenized individually in Qiazol and RNA extraction was performed. Using a 5ug input, samples were processed for microarray following the Affymetrix procotol. Samples were hybed to Rat 230 2.0 microarray chips.