Fig. 4.

An isolated bipolar β-gal⁺ cell from the cortex of a 2-week-old rat is shown in A (Vibratome section) and in B–D in adjacent semithin sections (arrows), either unstained (B) or after immunostaining for GABA (C) or BrdU (D). This cell was GABA immunoreactive (a marker of nonpyramidal neurons), as were many other isolated β-gal⁺ cells at this age, and displayed 12–25% BrdU-immunoreactive nuclear area. Three neighboring neurons (1–3) and blood vessels (asterisks) are shown as landmarks. Scale bars, 20 μm.