Effect of (4a) a novel 5-HT₃ receptor antagonist on chronic unpredictable mild stress induced depressive-like behavior in mice: An approach using behavioral tests battery

Background: The inconsistent therapeutic outcome necessitates designing and identifying novel therapeutic interventions for depression. Hence, the present study deals with the investigation of antidepressant-like effects of a novel 5-HT₃ receptor antagonist (4-phenylpiperazin-1-yl) (quinoxalin-2-yl) methanone (4a) on chronic unpredictable mild stress (CUMS) induced behavioral and biochemical alterations. Methods: Animals were subjected to different stressors for a period of 28 days. On day 15 after the subsequent stress procedure, mice were administered with (4a) (2 and 4 mg/kg p.o.), escitalopram (10 mg/kg p.o.), or vehicle (10 mL/kg p.o.) until day 28 along with the CUMS. Thereafter, behavioral battery tests like locomotor score, sucrose preference test, forced swim test (FST), tail suspension test (TST), and elevated plus maze (EPM) were performed. Biochemical assays like lipid peroxidation, nitrite levels, reduced glutathione (GSH), catalase, and superoxide dismutase (SOD) were estimated in the mice brain homogenate. Results: (4a) Dose dependently attenuated the behavioral alterations by increasing the sucrose consumption, reducing the immobility time in FST and TST, increasing the open arm number of entries and time in EPM. Furthermore, biochemical alterations were reversed by (4a) as examined by reduced lipid peroxidation and nitrite levels and elevated antioxidant enzyme levels like GSH, catalase and SOD. Conclusions: (4a) exhibits antidepressant potential by reversing the CUMS induced behavioral and biochemical changes in mice.