Analgesic and Central Nervous System Depressant Activities of Kolaviron (a Garcinia kola   biflavonoid complex)

This study evaluated the analgesic and CNS depressant activities of kolaviron (KV). The analgesic potential was measured using thermal (hot plate and tail withdrawal) and chemical (acetic acid-induced writhing) algesiometric tests, while the CNS depressant activity was evaluated by observing the reduction of locomotor and exploratory activities in the open- field the and whole board tests respectively at a doses of 50, 100 and 200mg/kg. The animals were also pre-treated with the ATP-K+ sensitive receptor antagonist, glibenclamide and L-arginine for the evaluation of the mechanism of its analgesic activity. The results showed that KV extract significantly (p<0.05) exhibited a dose dependent antinociceptive activity as shown by the prolongation of both the tail withdrawal and hot plate latencies in the thermal tests and a reduction in the number of writhes in the acetic acid-induced writhing test. Pre- treatment with glibenclamide and L- arginine was found to potentiate the previously observed analgesia as shown by greater reductions in the number of writhes in the acetic acid –induced writhing test. The extract at the same doses demonstrated a CNS depressant activity as indicated by a reduction in the number of head dips in the hole board test and a fall in the rearing, total locomotion and grooming frequencies in the open-field test. These results suggest the involvement of the nitrergic and ATP-K+ sensitive pathways in kolaviron analgesia and the possession of central nervous depressant activities