Quantitative gene expression analysis in a brain slice model: influence of temperature and incubation media.

We describe the RNA integrity (28S/18S ratio) and the messenger RNA (mRNA) expression of genes encoding glyceraldehyde 3-phosphate dehydrogenase (GAPDH), microtubule-associated serine/threonine kinase 2 (Mast2), and β-actin in cortical brain slices incubated for up to 24h in Ringer’s solution and Dulbecco’s modified Eagle’s medium (DMEM) at 25 and 37°C. Our data reveal an optimal temporal working window between 1 and 6h when slices are incubated in Ringer’s solution at 25°C that allows experiments related to gene expression dynamics to be performed more suitably than those carried out at 37°C. In addition, we show that reference gene expression may be modified in dynamic experiments and may compromise studies of gene expression.