Figure 7. Autoradiographs of tissue processed with ISHH with 35S-labeled mRNA for VIP in the coronal plane through the region of the thalamus (left column) and the superior colliculus (right column) throughout the development of the rat brain from birth (P0) to 60 days of age. Bar = 2 mm. ISHH was performed as previously described (71) . a: Control showing hybridization in the presence of 20X unlabeled probe. b: Post natal day (P) 0 rat pup. c,d: P7 rat pup. e,f: P14 rat pup. g,h: P21 rat pup. i,j: adult (P60) rat. Only the brain regions in the largest brain slices were labeled. Cx, cortex; DR, region of the dorsal raphe; SC superior colliculus; Thal, thalamus. Taken, with permission, from Hill et al, 1994 (71).