Antidepressant-like effects of methanol leaves extract of <I>Leptadenia hastata </I>(Asclepidiaceae) in mice

Depression is a serious disorder that affects people in all communities across the world, a major cause of disability and morbidity worldwide. The drugs used in its management are associated with adverse effects and delayed response, hence it’s important to look for antidepressant plants with proven advantages and favourable benefits.  Leptadenia hastata (Pers.) Decne belongs to the family Asclepidiaceae and is widely used in Tropical Africa as a vegetable due to its low toxicity and therapeutic benefits, it is used in the treatment of evil spirit, psychiatric disorders and hallucination. The aim of this study was to evaluate the antidepressant-like effect of the methanol leaves extract of Leptadenia hastata (LHME) and its fractions. Phytochemical screening and acute toxicity (LD50) study were done using standard procedures. Antidepressant-like effects of the LHME and its fractions was evaluated using the tail suspension test (TST) and forced swim test (FST). The intraperitoneal (i.p) median lethal dose was estimated to be > 5000 mg/kg. The LHME and Residual aqueous fraction (RAF) at dose 250-1000 mg/kg are significantly (P<0.05) and dose-dependently, while n-butanol fraction (NBF) at 400 mg/kg decreased the duration of immobility in the TST and FST respectively. There was no significant change in the number of squares crossed in the OFT. In conclusion, the L. hastata plant possesses antidepressant-like effects. Keywords: Depression, Forced swim test, Leptadenia hastata, Medicinal plant and Tail suspension test