Acute
reserpine and subchronic
haloperidol are animal models of
extrapyramidal disorders often used to study
parkinsonism, akinesia and
tardive dyskinesia. In humans, these usually irreversible and disabling
extrapyramidal disorders are developed by typical
antipsychotic treatment, whose pathophysiology has been related to oxidative damages development. So far, there is no treatment to prevent these problems of the psychiatric clinic, and therefore further studies are needed. Here we used the animal models of
extrapyramidal disorders cited above, which were performed in two distinct experiments:
orofacial dyskinesia (OD)/
catalepsy induced by acute
reserpine and subchronic
haloperidol after (experiment 1) and before (experiment 2) oral treatment with pecan shell aqueous extract (AE), a natural and promissory
antioxidant. When administered previously (exp.1), the AE prevented OD and
catalepsy induced by both
reserpine and
haloperidol. When
reserpine and
haloperidol were administered before the extract (exp.2), the animals developed OD and
catalepsy all the same. However, the orofacial parameter (but not
catalepsy) in both animal models was reversed after 7 and 14 days of AE treatment. These results indicate that, acute
reserpine and subchronic
haloperidol administrations induced similar
motor disorders, although through different mechanisms, and therefore are important animal models to study the physiopathology of
extrapyramidal disorders. Comparatively, the pecan shell AE was able to both prevent and reverse OD but only to prevent
catalepsy. These results reinforce the role of oxidative stress and validate the two animal models used here. Our findings also favor the idea of prevention of
extrapyramidal disorders, rather than their reversal.