Dexamethasone treatment reduces the exploratory activity of young Wistar rats

Abstract

Introduction. Dexamethasone (DEX) is a synthetic glucocorticoid with anti-inflammatory action used in the treatment of many diseases such as rheumatoid arthritis, asthma, allergies, and autoimmune diseases. Studies show that DEX can cause cognitive deficits in animals, which may result in reduced exploratory activity, impaired learning and spatial memory and increased anxiety. Objective. This study investigated the effects of DEX on exploratory activity, anxiety and spatial memory in young rats. Method. Young male Wistar rats were treated with dexamethasone phosphate at doses of 1 and 10 mg/kg/day for 7 days. On the 5th day of treatment, the open field test (OF) was performed to evaluate exploratory activity; on the 6th day, the elevated plus maze test (EPM) was performed to evaluate anxiety, and on the 7th day, the elevated T maze test (ETM) was performed to evaluate spatial memory. Results. In OF there was a 48% reduction in the number of total quadrants explored in the DEX group 10 mg/kg, 46% and 56% reduction in the number of central quadrants explored in DEX  1 and 10 mg/kg groups, respectively, and 40% reduction in the number of elevations in the DEX 10 mg/kg group, indicating that DEX decreased the exploratory activity on treated animals. In the EPM and ETM tests, there were no differences between the experimental groups, indicating that DEX did not interfere in the anxiety behavior and spatial memory. Conclusion. In the experimental conditions of this study, DEX decreased exploratory activity but did not alter anxiety behavior and spatial memory.