Phytochemical screening and central nervous system effects of ethanolic extract of Annona vepretorum (Annonaceae) in mice

Annona vepretorum Mart. (Annonaceae) is a native tree from Caatinga biome (semiarid region of Brazil) popularly known as “araticum” and “pinha da Caatinga”. This study was conducted to investigate the possible anxiolytic, motor and sedative effects of the crude ethanolic extract (Av-EtOH) on the central nervous system (CNS) in mice. The behavioral screening, open-field, elevated plus-maze, hole-board and rota-rod tests were used in this study. Av-EtOH (25, 50 and 100 mg/kg, p.o.) and diazepam (2.5 mg/kg, i.p.) were administered to different groups of mice and appropriate observations were made. Preliminary phytochemical analysis of the extract was also performed. A preliminary analysis of AvEtOH revealed that it contained phenols, steroids, terpenoids and flavonoids. The initial pharmacological screening revealed behavioral changes in animals at 0.5, 1, 2 and 4 h after Av-EtOH treatment, such as decrease of spontaneous activity, palpebral ptosis and decrease of response to the touch. Av-EtOH at dose of 25 mg/kg reduced (p < 0.01) the ambulation and rearing number and also increased the immobility time in open-field test. In elevated plus-maze test, the extract in all doses increased the time spent in closed arms and reduced (p < 0.05) the number of head dips in hole-board test at doses of 50 and 100 mg/kg. In addition, Av-EtOH did not impair motor coordination in rota-rod test. Taken together, the findings in this study suggest that A. vepretorum has sedative activity but does not affect the motor coordination of animals.