Effect of hydroalcoholic Echium amoenum extract on scopolamine-induced learning and memory impairment in rats

Context: Scopolamine, a muscarinic receptor antagonist, causes memory loss that resembles Alzheimer's disease (AD). Echium amoenum L. (Boraginaceae) is a famous medicinal plant of Iran that is traditionally used as a sedative and mood enhancer. Objective: This study evaluates the effect of hydroalcoholic extract of E. amoenum flowers on scopolamine-induced memory impairment in rats. Materials and methods: Fifty male Wistar rats were randomly divided into five groups. Control group received normal saline, model group received scopolamine (0.7 mg/kg, IP, daily for 21 days), and test groups received E. amoenum extract (50, 75, and 100 mg/kg, IP, daily for 21 days) 30 min before each scopolamine injection. The elevated plus maze (EPM), shuttle box, novel object and rotarod tests were performed after treatment. Brain levels of malondialdehyde (MDA) and total antioxidant capacity (TCA) were also determined. Results: Scopolamine-treated rats spent more time exploring the novel object compared to the control, and E. amoenum extract at all three doses significantly decreased the time spent exploring the novel object (p