| RESEARCH PAPER
|Year : 1997 | Volume
| Issue : 1 | Page : 15-19
Effect of acute and chronic haloperidol administration and apomorphine challenge on the behavioural parameters in rats
Stephen, ED Nsimba, JP Kelly, BE Leonard
Objective: To investigate the effect of acute and chronic haloperidol treatment and apomorphine challenge on the behavioural parameters in rats.
Methods: The study was done in male rats which were divided into 5 groups. They were treated with haloperidol in the doses of 0.3, 1.0, 3.0 and 10 mg/Kg i.p. The control animals received saline. The following parameters were studied: (a) Locomotor activity in home cage monitor. (b) Wood block test (catalepsy or Descent latency time). (c) Paw test (forelimb retraction time and hindlimb retraction time). (d) Effect of single injection of low dose apomorphine (0.05 mg/kg, s.c). challenge in rats after acute and chronic haloperidol treatment on locomotor activity in home cage monitor.
Results: Low dose haloperidol (0.3 mg/kg) had no effect on home cage locomotor activity, while higher doses decreased locomotor activity in rats after both acute and chronic treatment. Acute haloperidol treatment significantly increased descent latency at 3 and 10 mg/kg. It also significantly increased forelimb retraction time and hindlimb retraction time at 1, 3 and 10 mg/kg using the wood block (catalepsy) and paw test. Chronic haloperidol treatment significantly increased the descent latency time and hind limb retraction time at dose of 1, 3 and 10 mg/kg, i.p. A single injection of a low dose apomorphine (0.05 mg/kg, s.c.) challenge after acute and chronic haloperidol treatment further decreased the locomotor activity in home cage in all groups of animals.
Conclusion: Acute and chronic haloperidol treatment causes dopamine receptor sub-sensitivity in rats as observed by a decrease in home cage locomotor activity and their significant effect on hind limb retraction time.
Source of Support: None, Conflict of Interest: None