[Spasmolytic effect of Teucrium polium on virgin rat uterus]

ABSTRACT

Teucrium polium [locally known as chez or kalporeh in Khuzestan Province, Iran] is used traditionally as remedy for treatment of headache, convulsion and dysmenorrheal; and also its hypoglycemic, hypolipidemic and antibacterial effects has been reported. But its spasmolytic effect on uterine smooth muscle remained to be identified. The aim of the present study was to investigate the effect of Teucrium polium aqueous extract [TPAE] on virgin rat uterus contractions evoked by some stimulants. Freshly dried aerial parts of plant were extracted. Contractile responses were recorded isometrically in an organ bath containing Tyrode's or De Jalon solutions under 1g initial tension. Results indicated that extract [0.125, 0.25, 0.5, 1, 2, 4 and 8 mg/ml] reduced the uterus contractions induced by KCl [60mM], oxytocin [10mU/ml] and BaCl2 [4mM] dose dependently and significantly [P<0.0001]. The spasmolytic effect of extract was totally reversible in less than 10min. The spasmolytic effect of TPAE was unaffected by L-NAME [300 and 100 microM] in KCl- or oxytocin-induced contractions receptively. Spasmolytic effect of extract was unaffected by propranolol [1microM for 5 min] in KCl-induced contractions but, reduced significantly in oxytocin-induced contraction. In normal calcium De Jalon solution, the contractions-induced by BaCl[2], were more attenuated by extract than in calcium free solution. The data presented seem to suggest that the spasmolytic effect of Teucrium polium aqueous extract is partially induced via blocking the voltage dependent calcium channels and remaining effect is through involvement of the 3-adrenoceptors and stimulating the cAMP synthesis. In this inhibitory effect, NO is not involved