Se evaluó el efecto neurológico ejercido por el extracto hidroalcohólico (40%) obtenido de las hojas de Annona muricata (0,5 g/kg, vo) en ratones albinos ICR mediante pruebas tendientes a detectar posible actividad de tipo anticonvulsivante (electrochoque- pentilentetrazol), antidepresiva (nado forzado), hipnótica (potenciación de sueño barbitúrico) y ansiolítica (laberinto en cruz). Además se examinó la unión con radioligando del extracto a receptores de benzodiazepina, se efectuó el análisis fitoquímico y a la fracción alcaloidal obtenida se le aplicó la prueba del laberinto en cruz (0,5 g/kg, vo), según los resultados previos obtenidos con el extracto. Finalmente se evaluó la toxicidad del extracto (0,1-10 mg/mL) sobre las líneas celulares ECV-304 y k562. Los hallazgos sugieren que compuestos de tipo alcaloidal presentes en Annona muricata tendrían efectos de tipo ansiolítico (53% y 58% de tiempo y frecuencia de acceso a las zonas abiertas en la prueba de laberinto en cruz elevado), no vinculados la activación de receptores de benzodiacepinas y carentes de efectos citotóxicos in vitro. Estos datos ayudan a dar soporte al uso etnobotánico de esta especie.

The present study evaluated the neuropharmacological effect exerted by the hydroalcoholic extract (40%) obtained from leaves of Annona muricata (0.5 g/kg, po) in ICR albino mice using tests to detect anticonvulsant (electroshock-pentylenetetrazol), antidepressant (forced swimming test), hypnotic (barbiturate sleeping time) and anxiolytic activities (elevated plus maze). The putative binding of the extract to the benzodiazepine receptor by radioligand techniques was also studied. The phytochemical analysis of the extract led to the isolation of an alkaloid fraction that was evaluated in the elevated maze test (0.5 g/kg, po), in agreement with previous results obtained with the extract. Finally, it was assessed the toxicity of the extract (0.1-10 mg/ml) in cell lines k562 and ECV-304. The results suggest that alkaloid metabolites present in Annona muricata exert anxiolytic effects (53% and 58% of the time and frequency of access to open areas in the elevated plus maze), unrelated to the activation of benzodiazepine receptors and without cytotoxic effects in vitro. These data help support the ethnobotanical use of this plant specie.

Alguns efeitos farmacológicos da folha, talo e bulbo do alho foram investigados. Os extratos foram preparados por triturarão em solução etanólica 50%. Após evaporação a concentração final foi ajustada para 100 mg sólidos/ml. A dose utilizada foi de 1 g sólidos/kg por via oral. Vários efeitos (discretos) foram observados em comundongos, tais como diarréia, ptose e piloereção. Em ratos observou-se efeito hipoglicêmico do bulbo, efeitos analgésicos e hiperalgésicos dos três extratos e em ratos com hipertensão espontânea (mas não em ratos normotensos) um pronuciado efeito antihipertensivo de longa duração.

Extracts were prepared by trituration in H20/ ethanol (50/50 vol.). After evaporation the concentration of solids was adjusted to 100 mg/ml. A dose of 1 g solids/kg was administrated p.o. Various discreet effects were observed in the mouse, such as diarrhea, ptose and piloerection. In rats the buld decreesed slightly the blood sugar, all three parts showed analgesic and hyperalgesic properties (dependent on the interval after the administration of the extract). In spontaneously hypertensive rats (but not in normotensive rats) all three extracts shwed a pronounced and longlasting anti-hypertensive effect.