Ethnopharmacological communication Effects of the aqueous extract of Pimpinella anisum L. seeds on exploratory activity and emotional behavior in rats using the open field and elevated plus maze tests Maria Thereza Gamberini a,n , Domingos Sávio Rodrigues b , Daniela Rodrigues c , Victoria Bottino Pontes d Q1 a Department of Physiological Sciences of the Santa Casa de Sao Paulo School of Medical Sciences, R. Dr. Cesário Mota Júnior,112, Vila Buarque, São Paulo, SP, Brazil b Instituto de Botânica de São Paulo, Centro de Pesquisa Jardim Botânico e Reservas, Av. Miguel Estefano, 3031, Vila Água Funda, São Paulo, SP, Brazil c Santa Casa de Sao Paulo School of Medical Sciences, R. Dr. Cesário Mota Júnior, 61, Vila Buarque, São Paulo, SP, Brazil d A.C. Camargo Cancer Center, Rua Professor Antônio Prudente, 211, Liberdade, São Paulo, SP, Brazil article info Article history: Received 11 December 2014 Received in revised form 18 March 2015 Accepted 24 March 2015 Keywords: Pimpinella anisum L. Open field Elevated plus maze Rats Anxiety Habituation abstract Ethnopharmacological relevance: Pimpinella anisum L. is considered one of the first plants used for medicinal purposes. Pharmacological actions of the plant on the central nervous system have been proven but previous analyses have focused on anticonvulsant and neuroprotective actions. In traditional medicine worldwide, the use of Pimpinella is commonly recommended as a tranquilizer, although no scientific information supporting this use is available. Therefore, it was decided to investigate the central actions of the plant to observe behavioral responses, with an emphasis on the emotional component. Aim of study: To investigate the effects of the aqueous extract of Pimpinella seeds on exploratory activity and emotional behavior in rats using the open field and elevated plus maze tests. Materials and methods: Seeds of Pimpinella were extracted with distilled water, concentrated and freeze- dried yielding the aqueous extract(AE). Rats were divided into four groups: control(water 5 mL/kg, p.o.) and AE 0.5, 1.0 and 2.0 g/kg, p.o. Individual observations were performed in an open field and the parameters locomotor activity, rearing, grooming and defecation were recorded. In elevated plus maze test, rats were divided into four groups: control(water 5 mL/kg, p.o.) and AE 0.5,1.0 and 2.0 g/kg, p.o. The parameters arm entries, total time spent in open and closed arms; and total number of arrivals at the end of an open or closed arm were recorded for each rat. Results: Among the parameters assessed with the open field test, only rearing was reduced in the AE 0.5 g/kg group. When AE 1.0 g/kg was administered, only the initiation of exploratory activity was delayed, without impairing the animals' general activity. The highest dose of AE (2.0 g/kg) induced a reduction in the animals' habituation during the open field test within the same session, as evidenced by the maintenance of high levels of peripheral locomotion and rearing throughout the test. On the elevated plus maze test, no alterations were observed in the responses of the animals relative to controls for all doses tested. Conclusion: These results failed to support anxiety-related central action of the aqueous extract of Pimpinella seeds, invalidating popular beliefs regarding a tranquilizing effect. However, a habituation- related central action of the extract was demonstrated, suggesting action of bioactive compounds on central learning-related areas. The characterization of effects that may interfere with cognitive processes reinforces caution regarding indiscriminate consumption of the plant, especially in individuals with deficits, such as Alzheimer's Disease patients. & 2015 Published by Elsevier Ireland Ltd. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/jep Journal of Ethnopharmacology http://dx.doi.org/10.1016/j.jep.2015.03.053 0378-8741/& 2015 Published by Elsevier Ireland Ltd. n Corresponding author. Tel.: þ55 11 972925886; fax: þ55 11 33312008. E-mail address: maria.gamberini@fcmsantacasasp.edu.br (M.T. Gamberini). Please cite this article as: Gamberini, M.T., et al., Effects of the aqueous extract of Pimpinella anisum L. seeds on exploratory activity and emotional behavior in rats.... Journal of Ethnopharmacology (2015), http://dx.doi.org/10.1016/j.jep.2015.03.053i Journal of Ethnopharmacology ∎ (∎∎∎∎) ∎∎∎–∎∎∎