Is monofluoracetic acid the active neurotoxic principle in Palicourea marcgravii (St. Hill) leaves?

Acute intoxication of rats with the crude extract of Palicourea marcgravii (PM) and with monofluoraccetic acid (MFA) solutions was comapred since it has been reported that PM leaves contain monofluoreacetates (455 microng/g air-dried material). The neurotoxic signs produce by oral administration of PM and MFA were similar and included tonic-clonic seixures. The dose-reponse curves onstructed for the convulsant effects of PM and MFA were parallel and the CD50s were 630 mg/Kg (508-781) and 0.90 mg/Kg (0.76-1.06), respectively. These data suggest that the neurotixic signs produced by PM are the consequence of MFA presente in the plant leaves