An anticonflict effect of gamma-1-glutamyltaurine (Litoralon) in rats

Effects of gamma-1-glutamyltaurine (GT: Litoralon; Chinoin, Hungary) on rat's operant responses maintained under two types of negative reinforcement (avoidance) schedules: Sidman-type and discriminated avoidances and two types of positive reinforcement schedules and/or conflict schedules: differential water reinforcement of low rate (DRL 20 sec) and multiple fixed ratio 15/fixed ratio 15-punishment (MULT FR 15/FR 15-punishment) schedules were investigated to assess the central effects of GT. GT at 0.1-10 mg/kg i.p. induced no change in either the avoidance or DRL 20 sec responses. However, GT induced a prominent increase in the punished response (anticonflict effect) without eliciting a marked change in the non-punished response on the MULT FR 15/FR 15-punishment schedule. This behavioral change appeared not immediately, but gradually, when doses of more than 1 mg/kg were given; and a maximum level was achieved on days 3-6 and persisted for 7-14 days after the administration. The anticonflict effect of GT was synergistic with that of diazepam, a prototype antianxiety drug. No marked change in gross behavior was observed after GT. The present results suggest a possibility that GT has a central effect which correlates to the anticonflict effect.