The Inhibitory Effect ofHaloxylon salicornicumon Contraction of the Mouse Uterus

Abstract

Haloxylon salicornicum(H. salicornicum) is a plant that is frequently taken as a tea by Bedouin women in Egypt who are experiencing difficulties during pregnancy, as well as to provide relief from dysmenorrhoea. Despite its medical use, there has been no detailed evaluation of the effect of this plant on uterine tissue. Therefore, the initial aim of this study was to determine whetherH. salicornicumaffected the contraction of the mouse uterusin vitro. The crude aqueous extract ofH. salicornicumwas found to inhibit the spontaneous contractions of the uterus, with the effect being rapid in onset and completely reversible upon washout. Subsequent purification of the plant extract resulted in the identification of synephrine and N-methyltyramine, both of which were found to have inhibitory effects on the spontaneous contractions of the uterus. The EC50for the purified constituent identified as synephrine was 0.82 ± 0.24 μg/mL. The inhibitory activity of crudeH. salicornicum, as well as the isolated constituents, could be prevented by pretreatment of the uterus with theβ-adrenoceptor antagonist propranolol. In conclusion, the use ofH. salicornicumduring preterm labour appears to be justified, and its pharmacologic effect is consistent with it acting as aβ-adrenoceptor agonist.