The role of adrenergic receptors in nicotine-induced hyperglycemia in the common African toad (Bufo regularis

The role of adrenergic receptors in nicotine-induced hyperglycaemia has not been well studied in amphibians. Thus, this study investigates the effects of alpha and beta adrenergic receptor blockers in nicotine-induced hyperglycaemia in the common African toad Bufo regularis. Toads fasted for 24 h were anaesthetized with sodium pentobarbitone (3 mg/100 g body weight) intraperitoneally (i.p) and given intravenous (i.v) injection of 0.7% amphibian saline, or nicotine (50 mu g/kg), nicotine(50 mu g/kg i.v) 30 min after pretreatment with prazosin (0.2 mg/kg i.v), propranolol (0.5 mg/kg i.v) or combination of both prazosin (0.2 mg/kg i.v) and propranolol (0.5 mg/kg, i.v). Thereafter, blood samples were also collected from truncus arteriosus for estimation of blood glucose level using the modified glucose oxidase method. Nicotine caused significant increase (P