Study On The Pharmacodynamic Material Basis For Influencing The Activity Of Uterine Smooth Muscle Of N-butanol Part Of Leonurus Japonicus

Objective The pharmacodynamic material basis for influencing the activity of uterine smooth muscle of Leonurus japonicus have been studied by systemic chemical constituents and pharmacological experiments.Methods By using column chromatography over macroporous resin, MCI, siliea gel, Sephadex LH-20, and Rp C18, preparative thin layer chromatography, semi-preparative liquid chromatography, and recrystallization methods, the chemical components of bioactive fration of L. japonicus were isolated. Their structures were determined by spectroscopic and chemical techniques, including MS, UV, IR,1DNMR,2DNMR, and Marfey’s methods.The uterus in vitro uterus model of normal rats has been established and applied to detect the effects of the isolated compounds on the mobility, amplitude, tension, and frequency of uterine smooth muscle. The contraction curves of uterine smooth muscle were were recorder with sixteen channels physiological recording system.Results 1. Study on the chemical components of Leonurus japonicus Twenty-one compounds were isolated from L. japonicus, including ten steroidal alkaloid, five cyclic peptides, three flavone glycosides, three phenylpropanoid and aromatic compounds, four of them are new compounds.2. Study on uterine contraction activity of monomeric compound from Leonurus japonicus The effects on uterine smooth muscle of Leonurus japonicus showed dual effects of excitement and relaxation. In the test range, compounds 6,7,9 and 13 showed excitatory effects on the contractile activity of isolated uterus in normal rats. Specifically as follows:both high and medium doses of compound 6 could significantly increase average, minimum, and the contractile activity of uterine contraction; compound 13 could increase the average,maximum, minimum at low, middle, high doses, increasing the contractile activity of uterine contraction at high dose, compound 7 could rise minimum of the uterine contraction at low dose, increasing frequency, average and vitality of the uterine contraction at middle dose; Compound 9 could increase the average of uterine contraction at high dose.On the contrary, in the test range, Compounds 10,16-18 had an inhibition effect on the contractile activity of isolated uterus in normal rats, specifically as follows:compound 18 could reduce the vitality of the uterine contraction at low, middle, high dose, deseasing frequency, average of the uterine contraction at low, high dose, reducing the maximum of the uterine contraction at high dose. Compounds 17 could reduce frequency, average and the vitality of the uterine contraction at middle, high dose, reducing the maximum of the uterine contraction at high dose; Compounds 10 could reduce the frequency and the vitality of the uterine contraction at low dose, reducing frequency, the vitality, the maximum of the uterine contraction at high dose; Compounds 16 could reduce frequency and the vitality of the uterine contraction at low, middle, high dose, reducing the maximum of the uterine contraction at middle dose; Compounds 12 could the frequency of the uterine contraction at low dose, the above low, middle and high doses were respective as the final concentration of 1 μM,10μM,50μM, all the differences were statistically significant (P<0.05 or P＜0.01).Conclusions 1. Twenty-one compounds were isolated from L. japonicus, Among the compounds found, these were four new compounds, including two new cyclic peptide (1* and 2*), two special N-oxide steroidal alkaloid (3* and 4*)were discovered for the first time.2. The in vitro uterus experiment of normal rat indicated that there were two kinds of chemical constituents that had uterine contraction and relaxation effects separately in Leonurus japonicus. Cyclic peptides, steroidal alkaloid glycosides, leonurine were possible the material basis of uterine contraction by analysis of the structures of the compounds, flavone glycosides, steroid alkaloid were the main active constituents of relaxing the uterus.3. Cyclic peptides with uterine contraction activity have been abtained, which break through the traditional concept that motherwort alkaloid was the main pharmacodynamic material basis for uterine contraction.