Fig. 3. The 6-h exposure to desflurane, isoflurane, or sevoflurane increases apoptotic cell death in neonatal mice, compared with unanesthetized littermates that fasted. Representative low-magnification photomicrographs of coronal brain sections, obtained with laser confocal microscopy, at bregma −2.46 mm are shown, demonstrating the pattern of neuronal cell death. Brain sections from 7–8-day-old mouse pups were stained for the apoptotic cell death marker activated caspase 3 (bright green) after a 6-h exposure to the following: (A ) room air (control), (B ) 7.4% desflurane, (C ) 1.5% isoflurane, or (D ) 2.9% sevoflurane. Arrows mark clusters of dying neurons in neocortical layers II/III. The scale bar indicates 500 μm.