CRF in situ hybridization in the nucleus accumbens (A, B, C, D), bed nucleus of the stria terminalis/medial preoptic area (E, F, G, H), central nucleus of the amygdale (I, J, K, L), and posterior nuclei of the thalamus (M, N, O, P) in four vole species. Note the similarity in brain distribution of CRF mRNA in the various brain regions among the prairie voles (A, E, I, M), pine voles (B, F, J, N), meadow voles (C, G, K, O), and montane voles (D, H, L, P). Scale bar = 1 mm.