ABSTRACT
Background and Aim: 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 Method: 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
Results: 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
Conclusion: The findings of this study indicated that exercise had beneficial effects on learning and spatial memory independent of melatonin and its receptors
ABSTRACT
Testicular torsion is a medical emergency that requires surgical intervention to reperfuse the affected testis. Ischemia reperfusion injury is usually associated with proinflammatory cytokine generation and apoptosis of germ cells in the testes. In this study we investigate the effect of ghrelin on the proinflammatory cytokines levels and germ cell apoptosis in testicular ischemia reperfusion. 45 male rats were selected for the study and randomly divided into 3 groups, each containing 15 rats. Animals in the testicular torsion and ghrelin treated groups were subjected to unilateral 720 counterclockwise testicular torsion for 1 hr and then reperfusion was allowed after detorsion for 4 hr, 1 and 7 days. The ghrelin-treated group received intraperitoneal injection of ghrelin 15min before detorsion. The expression levels of bcl-2-associated X protein and proliferating cell nuclear antigen in testicular tissue in the different groups were detected by immunohistochemical assay and tissue cytokines interleukin-1beta, tumor necroses factor-alpha and interleukin-6 were measured using enzyme-linked immunosorbent assay. After being treated by ghrelin, the population of immunoreactive cells against BAX in the spermatocytes on day 7 after reperfusion significantly decreased when compared to tortion/ detortion-saline animals [p=0.024]. In contrast, PCNA expression in the spermatocytes and spermatogonia were not significantly different between tortion/ detortion-ghrelin and tortion/ detortion-saline groups on both experimental days. Administration of ghrelin significantly attenuated the testicular tumor necroses factor-alpha and interleukin-6 levels compared with the untreated animals, but had no significant effect on the level of interleukin-1beta. Ghrelin offers remarkable anti-inflammatory and anti-apoptotic effects in testicular ischemia reperfusion injury