title: Prunellae spica extract contains antagonists for human endothelin receptors.
abstract: Endothelin-1 (ET-1) is a powerful vasoconstrictor that contributes to blood pressure elevation. The biological effects of ETs are mediated by two receptors, namely, endothelin type A receptor (ET(A)R) and endothelin type B receptor (ET(B)R). Chinese herbal medicines (CHM) with antagonist activity for these two receptors were screened by establishing stable clones of CHO-K1 cells expressing high levels of human ET(A)R and ET(B)R, namely CHO-ET(A)R and CHO-ET(B)R.The aqueous extract of Prunellae Spica (P1) inhibited the binding of (125)I-ET-1 to ET(A)R and ET(B)R in CHO-ET(A)R and CHO-ET(B)R cells, respectively. P1 suppressed the ET-1-induced mobilization of intracellular  Ca(2+) . Through the alcohol fractionation of P1, the antagonists of human ET(A)R and ET(B)R were found to belong to different, separable ingredients and the antagonist of ET(A)R is more soluble in alcohol. The two antagonists were also effective in the test on human primary cells, HASMC and HUVEC. P1 successfully prevented the development of ET-1-associated hypertension in rats without further purification. These results indicate the presence of anti-hypertensive ingredients in P. Spica extract, at least through the inactivation of ET(A)R and/or ET(B)R.
authors: Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 11217, Taiwan, R.O.C.
authors: Chih-Ying
authors: CY
authors: Chen
authors: Low-Tone
authors: LT
authors: Ho
authors: Feng-Yuan
authors: FY
authors: Yang
authors: Chi-Chang
authors: CC
authors: Juan
authors: Lo-Chun
authors: LC
authors: Au
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D016466:CHO Cells / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D006224:Cricetinae; D004365:Drugs, Chinese Herbal / Q000494:pharmacology* / Q000627:therapeutic use; D065130:Endothelin A Receptor Antagonists; D065131:Endothelin B Receptor Antagonists; D019332:Endothelin-1 / Q000378:metabolism / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000517:prevention & control; D008517:Phytotherapy; D051381:Rats; D017208:Rats, Wistar; D044022:Receptor, Endothelin A / Q000378:metabolism; D044023:Receptor, Endothelin B / Q000378:metabolism; D012995:Solubility; D014867:Water
chemical_list: D004365:Drugs, Chinese Herbal; D065130:Endothelin A Receptor Antagonists; D065131:Endothelin B Receptor Antagonists; D019332:Endothelin-1; D044022:Receptor, Endothelin A; D044023:Receptor, Endothelin B; D014867:Water; D002118:Calcium