Baclofen attenuates harmaline induced tremors in rats

Recent experimental and clinical studies clearly suggest the role of gamma- aminobutyric acid (GABA) in the pathogenesis of tremors. The present study was undertaken to investigate the effect of baclofen, a GABA B receptor ago nist on harmaline induced tremors. Four groups of female Wistar rats weighi ng 100 +/- 15 g were injected with harmaline (10 mg/kg, intraperitoneally) for inducing experimental tremors. The animals in groups 2, 3 and 4 were gi ven baclofen by gavage at doses of 2.5, 5 and 10 mg/kg, respectively, half an hour before harmaline administration, whereas, the rats in group 1 serve d as control and received water. The latency of onset, intensity and durati on of tremor and electromyographic (EMG) responses were recorded. Treatment with baclofen resulted in a dose dependent decrease in the intensity of tr emor. Our EMG study also revealed a significant decrease in the amplitude o f tremors in baclofen treated rats. A highly significant increase in latenc y of onset of tremor was observed in the rats treated with high dose (10 mg /kg) of baclofen only. This study clearly suggests beneficial effects of ba clofen in harmaline induced tremors. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.