Prunellae spica extract contains antagonists for human endothelin receptors

• Published in: The American journal of Chinese medicine (1979) Vol. 41; no. 1; p. 85
• Main Authors: Chen, Chih-Ying, Ho, Low-Tone, Yang, Feng-Yuan, Juan, Chi-Chang, Au, Lo-Chun
• Format: Journal Article
• Language: English
• Published: Singapore 2013
• Subjects: Animals; Blood Pressure - drug effects; Calcium - metabolism; CHO Cells - metabolism; Cricetinae; Drugs, Chinese Herbal - pharmacology; Drugs, Chinese Herbal - therapeutic use; Endothelin A Receptor Antagonists; Endothelin B Receptor Antagonists; Endothelin-1 - metabolism; Endothelin-1 - physiology; Humans; Hypertension - prevention & control; Phytotherapy; Rats; Rats, Wistar; Receptor, Endothelin A - metabolism; Receptor, Endothelin B - metabolism; Solubility; Water
• ISSN: 0192-415X; 1793-6853
• DOI: 10.1142/S0192415X13500079

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.