Blood sugar concentrations during ketamine or pentobarbitone anesthesia in rats with or without alpha and beta adrenergic blockade.

Plasma glucose concentrations were measured in: 1) conscious and anesthetized rats during an iv glucose tolerance test (IVGTT) and 2) conscious and anaesthetized phentolamine/propranolo] blocked rats during an IVGTT. Anesthesia was induced with ketamine (120 mg . kg-1) or pentobarbitone (60 mg - kg-1) ip at -30 min of the beginning of the IVGTT, which was followed by 2 injections of the anesthetic agents at intervals of 30 min. Propranolol (2 mg . kg-1) was given ip at -25 and -5 min. An iv infusion of phentolamine (0.015 mg . min-1) was started at -20 min and continued up to the end of the experiment. During the IVGTT, the anesthetized rats showed a moderate hyperglycemic response to glucose load compared to conscious animals (ketamine: p 0.05). While in ketamine anesthetized rats the increased glucose response was abolished by adrenergic blockade (p