A rapid and nearly quantitative method for the direct analysis of steady-state mRNA levels in microgram quantities of frozen mammalian brain is described. Briefly, tissue punches 0.5-1.0 mm in diameter were sampled from 250-microns-thick cryostat sections of rat brain (approximately 50-200 micrograms tissue). The samples were homogenized in 50 microliters of a denaturing gel loading buffer and applied directly to a 2.2 M formaldehyde-agarose gel for electrophoresis and subsequent RNA blot analysis. The method is extremely rapid, results in excellent recovery of intact RNA, and allows the direct assay of mRNA levels in discrete subregions of the mammalian brain.