Carnosine (β-alanyl-L-histidine) increases the efficacy of learning under conditions of oxidative stress related to the development of conditioned response with negative reinforcement

Previously, using in vivo models hystidine containing dipeptide carnosine (β-alanyl-L-hystidine) was shown to inhibit the development of oxidative stress induced by such effects like hypoxia, ischemia and neurotoxin administration. These studies showed that animals having undergone oxidative stress in the settings of carnosine administration preserve habits developed in open field, holeboard and Morris water maze. We investigated the effect of carnosine on cognitive processes in brain in the settings unrelated to the action of damaging factors. Carnosine administration prevented the increase of lipid hydroperoxides levels and increased the antioxidative state of the brain in rats under development of active avoidance response in the shuttle box. In these settings the acceleration of habit development and the increase in ratio of successfully trained animals was reported. At the same time the level of glutamate—the main transmitter amino acid related to the function of brain’s flexibility—in the brain of rats receiving carnosine increased. The results obtained indicate the nootropic properties of carnosine.