Effect of khat leaves extract (Catha edulis) on the excitability of frog gastrocnemius.

Abstract

This study was held on the isolated excitable tissue of frog's gastrocnemius muscle. Experiments were down by determining the dose dependent of leaves of khat extract. Work down in accordance with personal presupposition since reported that khat have psycho stimulant effects accordingly we thought khat might have effects on systemically biology that mediated by chticol amines. Results showed the effect of khat leaves extract on excitability of muscle contraction that was easily attested when the electrical stimuli were applied either through the nerve or directly to the muscle. Whereas khat treatment showed a significant increase in the contraction period of the gastrocnemius muscle and both of the relaxation periods and half relaxation time were shortened. Also it was found that pretreatment by khat leaves extract caused changes in the tension output, increased the height of effect intensity with prolonged the contraction period, while the latent period was decreased and reduced slightly the half relaxation period of the twitch comparison with the normal control muscle. These experimental results indicated that khat had highly stimulant effects on muscle, whereas caused liberation of thermoenzymatic and chemical energy during contraction which converted into mechanical energy, which manifested its self as work.