Planta Med 2001; 67(7): 605-608
DOI: 10.1055/s-2001-17355
Original Paper
Pharmacology
© Georg Thieme Verlag Stuttgart · New York

Intracellular Calcium Mobilization as a Target for the Spasmolytic Action of Scopoletin

E. J. Oliveira, M. A. Romero, M. S. Silva, B. A. Silva, I. A. Medeiros*
  • Laboratório de Tecnologia Farmacêutica, Universidade Federal da Paraíba, João Pessoa, Brazil
Further Information

Publication History

October 13, 2000

December 16, 2000

Publication Date:
24 September 2001 (online)

Preview

Abstract

The coumarin scopoletin was isolated in a pure form from the roots of Brunfelsia hopeana Benth. (Solanaceae). In isolated rat aortic rings, scopoletin (26-520 μM) inhibited to approximately the same extent the contractions induced by a variety of substances, including phenylephrine, potassium chloride, serotonin and PGF2 α. The effect of the coumarin on phenylephrine-induced contractions was not affected by endothelium removal or NO-synthase blockade by L-NAME (100 μM). Scopoletin (78 - 590 μM) antagonized in a concentration-dependent manner (IC50 = 300 ± 20 μM, n = 5), transient contractions in Ca2+-free media induced by noradrenaline, but not those induced by caffeine. Also, scopoletin did not interfere with the refilling of noradrenaline-sensitive intracellular calcium stores. It is suggested that the non-specific spasmolytic action of scopoletin can be attributed, at least in part, to its ability to inhibit the intracellular calcium mobilization from the noradrenaline-sensitive stores.

References

Prof. Isac Almeida de Medeiros

Laboratório de Tecnologia Farmacêutica

Universidade Federal da Paraíba

Caixa Postal 5009

58051-970 João Pessoa, PB

Brazil

Email: isacmed@netwaybbs.com.br

Fax: +55-83-216-7511 or 83-216-7366