Interaction between melatonin and exercise in the spatial memory and learning performance in rats

Physical exercise and melatonin have considerable effects on cognitive functions such as spatial memory and learning performance. The aim of this study was to clarify the possible interaction between the exercise and melatonin and its effects on spatial memory and learning performance in rats.
Material and In this experimental study groups of rats underwent 2 interventions. In experiment 1, Wistar rats were divided into groups (7 in each group), as follows: sedentary-vehicle, treadmill exercise-vehicle, and sedentary-melatonin and treadmill exercise-melatonin. In experiment 2, groups were designed as; sedentary-saline, treadmill exercise-saline, sedentary-lozindole and treadmill exercise-lozindole (M1 and M2 melatonin receptor blocker). The animals received drugs and vehicles intraperitoneally, 30 minutes before treadmill exercise, every day for fifteen consecutive days. Then their learning and spatial memory performance was evaluated using Moris water maze task. Data analysis was performed by two way analysis of variance.
Melatonin significantly attenuated learning and memory performance in both exercised and non-exercised rats. Blocking the melatonin receptors by lozindole improved spatial memory in the rest condition, but had no significant effect on the learning and spatial memory after exercise.
The findings of this study indicated that exercise had beneficial effects on learning and spatial memory independent of melatonin and its receptors.