Regulation of feline cpg15mRNA expression in the LGN during normal development. In situ hybridization (using an 35S-labeled antisense riboprobe) was performed on brain sections at the level of the LGN (blackarrows) from animals of the indicated ages. Results are presented in dark field. Sections were cut either in the horizontal [E43, E52, P0; anterior (A) and medial (M) are indicated] or coronal [P10, P25, P40, P91; dorsal (D) and M are indicated] plane. The whitearrow in E43 and P0 is the visual cortex. Scale bar, 1 mm.