Antipsychotic evaluation of ethanol extract of Tapinanthus globiferus A. rich grown on Vitellaria paradoxa host in mice

Abstract

Tapinanthus globiferus has evolved to mimic the foliage of Vitellaria paradoxa as a host tree. It is used locally for the treatment of various diseases such as diabetes, stroke, headaches, insomnia, migraines, pains and schizophrenia. Though, patients with psychosis often use natural medicines and yet it is unclear whether these are
safe and effective. This study aimed to evaluate the antipsychotic activity of ethanol extract of Tapinanthus globiferus grown on Vitellaria paradoxa in mice.
Phytochemical screening and acute toxicity studies were carried out using standard
methods. The antipsychotic activity of the extract was evaluated using haloperidolinduced
catalepsy, apomorphine-induced climbing behaviour and tail suspension
test in mice. The studies revealed that, the extract contained valuable biological
active compounds with LD50 of 1,300 mg/kg i.p. which are slightly toxic.
Tapinanthus globiferus offered significant effect in duration of haloperidol-induced
catalepsy at 350 mg/kg, apomorphine-induced climbing behaviour at 87.5 and 175
mg/kg and no effect in duration of immobility in tail suspension in mice at all doses
compared to control. The observed effect of the extract on haloperidol-induced
catalepsy and significant reduction in climbing behaviour induced by apomorphine
showed that the extract may have effect on dopamine receptors and antipsychotic
agents antagonise dopamine D2-receptors. The investigation revealed that extract
of T. globiferus contained active constituents which have antipsychotic effect in
mice.