4.5. RNA extraction and slot blotting

Total RNA from tissue was isolated by the CsCl-Gradient method (Davis et al. 1986). Total RNA from cultured cells was isolated using TRIzolTM reagent (Life Technologies, Grand Island, NY) as recommended by the manufacturer. Slot blot of RNA samples was prepared as described by Solin et al. (1990) and hybridized with 32P-labelled pCAT DNA. Control probing of the blots was performed with nick-translated glyceraldehyde-3-phosphate dehydrogenase cDNA (GAD, AC: X02231). Densitometric analysis was used to quantify the mRNA signals of the samples.