Fig. 3.  Jasplakinolide attenuates isoflurane-mediated reduction in dendritic filopodial spines and enhancement of apoptosis in DIV4–7 neurons (4–7 days in vitro ). Primary neurons (DIV4–7) were exposed to 1.4% isoflurane (Iso) for 4 h with and without pretreatment with the actin cytoskeleton stabilizer jasplakinolide (Jasp) (1 h, 1 μm) and incubated with antibodies for drebrin (neuronal F-actin binding protein) (A –C , quantitation shown in D ), the apoptotic marker cleaved caspase-3 (Cl-Csp3) (E –G , quantitation shown in H ), and the nuclear marker DAPI (4′,6-diamidino-2-phenylindole). Pretreatment with jasplakinolide significantly (C , n = 4–6; *P = 0.0144 vs.  isoflurane) attenuated isoflurane-mediated decreased (B , # P = 0.0337 vs.  basal) in drebrin immunofluorescence and significantly (n = 4–6; *P = 0.001 vs.  isoflurane) decreased Cl-Csp3 expression (G ). Drebrin (green pixels) along dendrites is normalized to DAPI (blue pixels) and Cl-Csp3 (red pixels) is normalized to DAPI. Scale bar, 10 μm. Error bars, SEM.