Distribution of apoptotic cell death in gray matter and white matter of fetal nonhuman primate brain. This figure presents computer plots displaying the location of activated caspase-3 (AC3)–positive profiles in sections at a midrostrocaudal (A and B) or cerebellar/brain stem (C and D) level of a fetal control brain (A and C), or a fetal brain exposed to isoflurane (ISO; B and D). Red dots = neuronal profiles; white dots = glial (oligodendrocyte) profiles. The distribution pattern is similar in the control and isoflurane-exposed brains, but the density of stained profiles is much greater in the isoflurane-exposed sections. Neuronal populations preferentially affected include those in the frontal (FC) and temporal (TC) cortices, the caudate nucleus (CN), putamen (Pu), amygdala (Am), and in all folia of the cerebellum. Vulnerable oligodendrocytes were distributed diffusely throughout white matter regions in a pattern corresponding to the location of major axonal pathways, such as the corona radiata (CR), centrum semiovale (CSO), internal capsule (IC), anterior commissure (AC), optic chiasm (OC), and cerebellar peduncle (CP).