Abstract

The effect of quinine commonly used for the treatment of chloroquine resistant cases and cerebral malaria on exploration in Wistar rats was investigated. Adult male rats (n= 27), weighing between 150 and 190 g were randomly selected into two treatments groups (n=9) and control (n=9). Each control rat in Group I received intramuscularly injection of physiological saline. The rats in Group II were injected intramuscularly with quinine, 20 mg/kg for a starting dose, followed by 10 mg/kg 8 hourly for 7 days. The Group III rats received the same treatment as Group II, but were subjected to a withdrawal period of one week after the treatment. The exploration and locomotion of treated rats were significantly suppressed (P < 0.05) by quinine. The frequency of line crossing reduced significantly from 30.8 ± 5.7 in Group I to 2.2 ± 0.93 in Group II and 2.5 ± 1.1 in Group III rats. The frequency of hinding also reduced significantly from 7.4 ± 1.3 in group I to 0.7 ± 0.4 in Group II and 0.9 ± 0.3 in Group III. The marked decrease observed in exploratory activities in the treated groups might be the consequence of degeneration of cerebellar cortex.

Key words: Quinine, locomotion, exploration, suppression, Wistar rats.