The (8)17,12E,14-labdatrien-18-oic acid (labdane302), labdane-type diterpene isolated from Xylopia langsdorffiana St. Hil. & Tul. (Annonaceae) relaxes the guinea-pig trachea

Revista Brasileira de Farmacognosia

Silva, Marcelo S. da¹  Universidade Federal do Piauí, Teresina, Brasil¹  Universidade Federal da Paraíba, João Pessoa, Brasil¹  Ribeiro, Luciano A. A.¹  Silva, Bagnólia A. da¹  Tavares, Josean F.¹  Andrade, Nilza C. de¹ 

关键词: Xylopia langsdorffiana;    Annonaceae;    labdane;    diterpene;    guinea-pig trachea;    relaxation.;   

DOI  :  10.1590/S0102-695X2007000200011

来源: Sociedade Brasileira de Farmacognosia

【 摘 要 】

Xylopia langsdorfiana St. Hil. & Tul. is popularly known as "pimenteira-da-terra" in Southeast of Brazil. The fractionation of the ethanol extract obtained from the stem-bark of this species yielded a labdane-type diterpene identified as 8(17),12E,14-labdatrien-18-oic acid, referred here as labdane302. In this study, we investigated the effect of labdane302 in guinea-pig trachea. labdane302 relaxed the basal tonus of trachea rings with EC50 value of 6.7 ± 0.5 x 10-8 M. The diterpene labdane302 relaxed the pre-contracted rings by carbachol 10-6 M both in the presence (EC50 = 1.4 ± 0.7 x 10-5 M) and absence of functional epithelium (EC50 = 1.5 ± 0.3 x 10-5 M), as well as pre-contracted by KCl 18 mM or 60 mM, presented EC50 values of 2.3 ± 0.4 x 10-7 M and 1.8 ± 0.8 x 10-5 M, respectively. This relaxant effect, upon contractions induced by KCl 18 mM, was more potent as well as more efficient than the one presented with KCl 60 mM pre-contracted rings. The labdane-type diterpene labdane302 shows the relaxant effect in isolated guinea-pig trachea, pre-contracted or upon basal tonus, apparently without participation of epithelium-derived relaxant factors, but apparently involving activation of K+ channels.

【 授权许可】

Unknown