Alterations in rat carbohydrate metabolism induced by canatoxin as a probable consequence of primary hypoxia

1. Canatoxin, a protein displaying lipoxygenase-activating properties isolated from Canavalia ensiformis seeds, induces hypoxia and hyperglycemia in male rats. 2. Liver glycogen, blood glucose and lactate levels were measured in male and female rats after canatoxin (50 mU, iv) injection. Increased levels of serum glutamic oxaloacetic transaminase activity were used as an indicator of hepatic injury. 3. There was no sex-related difference observable during canatoxin-induced hypoxia but male and female rats did show different patterns of metabolic change and hepatic injury after toxin administration. Increased blood glucose and lactate levels, liver glycogenolysis and hepatic injury were observed in male rats while female rats showed only hypoglycemia and glycogenolysis. 4. Pretreatment of male rats with either glucose, diazepam or hexamethonium abolished both the hypoxia and hepatic injury and the metabolic alterations produced by toxin injection. 5. The results suggest that the metabolic alterations and hepatic injury detected after canatoxin injection may be a consequence of primary hypoxia.