Relaxant and Antispasmodic Activities of Aqueous Extract from <i>Thymus algeriensis</i> Boiss. and Reut.

Abstract

<em>Thymus algeriensis</em> have been vastly utilized for intestinal disorders. The purpose of this investigation was to scrutinize the probable mechanism for its utilization in the spasm disorder. Aqueous extract of this medicinal plant (AqTA) was tested<em> in vitro</em> on rat and rabbit jejunum. The extract produced relaxation of rabbit jejunum. This relaxation does not depend on the adrenergic pathway, the AqTA induces inhibition irrespective of the presence or absence of adrenergic inhibitors. AqTA engendered a concentration-dependent (0.1-5 mg/ml) relaxation of carbamylcholine chloride (CCh) and K⁺ provoked tones in rat intestine with IC₅₀ values of 2.06 ± 0.26 and 3.55 ± 0.48 (mg/ml) respectively. This extract likewise induced a dosedependent (0.1-3 mg/ml) rightward shift in the CCh and Ca⁺⁺ dose-response curves. The AqTA alone has decreased more significantly the percentage of contraction of rat jejunum than the AqTA pre-incubated with atropine or hexamethonium then contracted with KCl; but there is no significant difference by those pre-incubated with methylene blue or L-NAME. When the intestine was pretreated with nifedipine and contracted by CCh, the antispasmodic effect provoked by AqTA with and without pre-incubation with nifedipine is statistically not significant. In conclusion AqTA acts possibly on the voltage dependent Ca⁺⁺ channel and cholinergic receptors but did not act on adrenergic receptors, NO and guanylatecyclase pathway. This investigation may explicate some of its traditional utilization in gut illnesses.