Oral administration of Excitin-1 (β-alanyl-Lleucine) alters behavior and brain monoamine and amino acid concentrations in rats

We previously demonstrated that β-alanyl-branched chain amino acids have excitatory effects. Therefore, we named β-alanyl-L-leucine, β-alanyl-L-isoleucine and β-alanyl-L-valine as Excitin-1, -2, and -3 , respectively. Since there is little known about the effects of Excitins, we clarified whether oral administration of Excitin-1 affects behavior in rats, alters the monoamine and amino acid levels in the central nervous system, whether Excitin-1 is incorporated into the brain, and how long it remains in the blood. Excitin-1 increased motor behavior, increasing the distance of path and number of rearings in the open field. Excitin-1 influenced some monoamine and amino acid levels in the cerebral cortex and hypothalamus. Following oral administration, Excitin-1 was detected in the cerebral cortex, hypothalamus, hippocampus and olfactory bulb. In the plasma, Excitin-1 and its metabolites β-alanine and L-leucine were recorded. The present study demonstrated that Excitin-1 was incorporated in the brain and promoted behavioral changes in rats.