Planta Med 2003; 69(8): 715-719
DOI: 10.1055/s-2003-42788
Original Paper
Pharmacology
© Georg Thieme Verlag Stuttgart · New York

Albaconol from the Mushroom Albatrellus confluens Induces Contraction and Desensitization in Guinea Pig Trachea

Wei-Min Yang1 , 2 , Ji-Kai Liu1 , Chen Qing2 , Yi-Dan Liu3 , Zhi-Hui Ding1 , Zhi-Qiang Shen2 , Zhi-He Chen2
  • 1Kunming Institute of Botany, The Chinese Academy of Science, Kunming, P. R. China
  • 2Yunnan Pharmacological Laboratories of Natural Products, Kunming Medical College, Kunming, P. R. China
  • 3Drug Research & Development Department, Kunming Pharmaceutical Co., Kunming, P. R. China
We wish to acknowledge the financial support from the National Natural Science Foundation of China (30225048)
Further Information

Publication History

Received: December 20, 2002

Accepted: March 31, 2003

Publication Date:
06 October 2003 (online)

Abstract

The contraction and desensitization induced by albaconol and the influence of capsazepine, capsaicin and extracellular Ca2+ were investigated to see whether the actions were mediated via a specific VR receptor in guinea pig trachea spiral strips in vitro. Both albaconol and capsaicin were contractors of tracheal smooth muscle, but albaconol was not so potent as capsaicin, with -log (M) EC50 values of 4.23 ± 0.18 (n = 10) and 7.33 ± 0.21 (n = 10) respectively. 2.5 μM capsazepine competitively antagonized the contractile response to albaconol and capsaicin. Albaconol increased the contraction induced by a low dose of capsaicin (10-10 to 10-9 M), but non-competitively antagonized the contraction induced by a high dose of capsaicin (10-8 to 10-3 M). Either albaconol (1 or 100 mM) or capsaicin (3 or 10 μM) was able to desensitize the isolated guinea pig bronchi to subsequent addition of albaconol. Capsazepine (5.0 μM) significantly prevented the desensitization induced by either albaconol (1 or 100mM) or capsaicin (3 or 10 μM). Extracellular Ca2+ was essential for albaconol to induce excitation, but it did not affect albaconol- or capsaicin-induced desensitization. In summary, the results from the present study suggest that albaconol induces contraction and desensitization of guinea pig trachea in vitro as a partial agonist for VR.

References

Dr. Ji-Kai Liu

Kunming Institute of Botany

The Chinese Academy of Science

Kunming 650204

P. R. China

Phone: +86-871-5216327

Fax: +86-871-5150227

Email: jkl@public.km.yn.cn