Antagonistic Effect Studies Of Pyrazole Carboxylic Acid Compounds On Endothelin Receptor

Objective:Endothelin receptor antagonists can treat many diseases such as hypertension、pulmonary hypertension、cancer、congestive heart failure etc. In this study, we base on the structures of endothelin receptor antagonists appear on the market, we change their structures and synthesize a series of pyrazole carboxylic acid compounds (TY608series of compounds). We evaluate receptor binding capacity and selectivity between compounds and ETRA、ETRB by molecular docking method and screening the activity of compounds in experiment. we expect to discover effective durgs to treat diseases.Methods:1. We select ETRA、 ETRB as masculine receptors. Bosentan Enrasentan、Tezosentan、Ambrisentan、Atrasentan. Clazosenta、Darusentan、 Sitasentan、Edonentan、Avosentan and BQ788are selected as masculine ligands. Ten molecules are selected as feminine ligands. TSH、β2adrenaline receptor、a-2A adenosine receptor、5-HT-1A、5-HT-1B、5-HT-1D、5-HT-1E、5-HT-1F and D2、 D3receptors are selected as feminine receptors. We use Schrodinger2008software and use the Glide module for molecular docking. We investigated the binding capacity and selectivity of the interaction between TY608series of compounds and the receptor by docking scores and predict the activity of compounds.2. We use isolated thoracic aortic rings to evaluate the activity of TY608series of compounds in vitro experiments and evaluate antagonistic effect on endothelin induced vasoconstriction in different drug concentrations(0.1μug/ml、1μg/ml、10μg/ml). We Calculate inhibitory efficiency of compounds in different drug concentrations.3. We use endothelin lethal test to evaluate the activity of TY608series of compounds in vivo experiments. Ig administration of a dose of100mg/kg,four hours later, Intravenous injection of10nmol/kg endothelin. Record number of deaths of mice in twenty minutes. Mortality of mice is used to evaluate endothelin antagonistic effect of compounds.Results:1. Molecular docking results:TY608series of compounds have better binding ability with ETRA、ETRB, TY608-2.3、7、12、16compounds have better binding ability with ETRB. TY608-1、4、6、10、11、13、15、18compounds have better binding ability with ETRA、ETRB. TY608series of compounds have better binding ability with5-HT-1A、5-HT-1B、5-HT-1D、D2、D3、a-2A and β2receptor. TY608series of compounds may affect many targets and have nonselective effect on receptor2. In vitro screening test results:compared with the control group, inhibitory effect of TY608series of compounds have no statistics significance in low concentration of0.1μg/ml. TY608-2、TY608-4、TY608-5and TY608-16have better inhibitory effect in middle concentration of1μg/ml (P<0.05). TY608-1、TY608-2、 TY608-3、TY608-4、TY608-5、TY608-6、TY608-7、TY608-9、TY608-10、TY608-11、 TY608-12、TY608-13、TY608-14、TY608-15、TY608-16、TY608-17、TY608-18have better inhibitory effect in high concentration of10μg/ml (P<0.01or P<0.05).3. In vivo screening test results,compared with the control group, TY608-10、 TY608-12have effective inhibitory effect on endothelin (P<0.01), TY608-2have better inhibitory effect on endothelin (P<0.05)Conclusion:According to theoretical and experimental studies on TY608series of compounds, we find that TY608-2、TY608-10、TY608-12not only have better selective effect on ETRA、ETRB in theoretical study but also have better antagonistic effect on endothelin-1induced vasoconstriction in experimental study, especially TY608-2have strong antagonistic effect in vivo and vitro screening efficacy experiments. So we obtain better results from theoretical and experimental studies.