Figure 4

Figure 4

Glyoxylate’s rescue mechanism is not fully explained by cyanohydrin formation. Dose dependent survival of 5 dpf zebrafish in the presence of (A) scavengers (3 fish per well, N = 6 wells for each condition) or (B) cyanohydrin-forming molecules 20 h after exposure to 20 µM KCN (3 fish per well, N = 6 wells for each condition with the exception of alpha-ketobutyrate, N = 3). Data presented as mean ± SEM. HCP was 100% lethal at the highest dose (1 mM) and this data point was removed to preserve an accurate dose–response curve. (C) Continuous-wave near-infrared spectroscopy (CWNIRS) monitoring changes in concentrations of deoxygenated (RHb), oxygenated (OHb), and total (THb) hemoglobin. The rabbits were exposed to a sublethal dose of 10 mg i.v. NaCN for 60 min. At 60 min, subjects received equimolar doses of glyoxylate or (D) alpha-ketoglutarate (100 mg or 147 mg respectively). Results shown are typical of the response seen by CWNIRS in animals treated with cyanide and glyoxylate.