Fig. 3

Effects of heat shock preconditioning on cell death in zebrafish brain and eye tissues after sublethal hypoxia treatments.

A: The average number of TUNEL-positive nuclei per unit volume in the eye and brain following 100 min of hypoxia at 48 hpf and 8 hours of recovery in normoxic media. Asterisks indicate statistically significant differences between values obtained from non-preconditioned (No PC) embryos and embryos preconditioned with a heat shock at 34 hpf (PC). Error bars are the SEM. B: TUNEL positive cells in representative images of eye (upper panels) and brain (lower panels) regions after hypoxia. Dashed lines indicate the region in which nuclei were counted. Scale bars are 100 μm. Asterisks mark the dorsal, anterior aspect of the embryos. C: Hsp70 and Hsp27 immunostaining of brain (left panels) and eye (right panels) tissues. Arrows highlight regions showing increased Hsp70 staining intensity of heat shock preconditioned (PC) tissues compared to non-preconditioned (No-PC) controls. Increases in Hsp27 staining intensity are also evident throughout the preconditioned tissues. Scale bars are 100 μm.