Background: Medicinal plants
contain physiologically active principles that over the years have been
exploited in traditional medicine for the treatment of various ailments. Objectives and Methods: This study
aimed to investigate the effects of the methanolic extract of Pausinystalia
yohimbe bark (5 mg/ml) on isolated rabbit aortic strip and rat uterus. Results: methanolic extract of P.
yohimbe bark (5 mg/ml) produced relaxation of the phenylephrine precontracted-rabbit
aortic strip. This relaxation may be resulted through nitric oxide (NO), since
the pretreatment of the isolated rabbit aortic strip with methylene blue
inhibited the NO-mediated relaxation. Moreover, theextract exhibited
relaxation of rat uterine muscles, which appeared to be not mediated by activation
of β2-adrenoceptors and/or
H2 receptors, since the relaxant
effect continued even after the pretreatment of the tissue with
propranolol and ranitidine respectively. Conclusion: The obtained results
revealed that methanolic extract of P. yohimbe bark caused relaxation
of both isolated rat uterus and rabbit
aortic strip through facilitating the role of endogenous compounds such as NO.
Cite this paper
Hassan, H. , Eldin, I. , Ahmed, E. , Mohamed, A. and Sirag, N. (2013) Effects of methanolic extract of yohimbe bark (Pausinystalia yohimbe) on isolated rabbit aortic strip and rat uterus. Health, 5, 1016-1020. doi: 10.4236/health.2013.56135.
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