The relaxant effect of methanolic extract of yohimbe bark (Pausinystalia yohimbe) on rabbit corpus cavernosum smooth muscles

Mohamed Hassan Hozeifa, Imad Eldin Mohamed Taj Eldin, Mohamed Mohamed Ahmed Elhadi, Hassan Mohamed Abd Elwahab, Sirag Elteyb Nizar

Department of Pharmacognosy, Faculty of Pharmacy, University of Gezira, Wad Madani, Sudan.
Department of Pharmacology and Toxicology, Medicinal and Aromatic Plant Research Institute, National Center for Research, Khartoum, Sudan.
Department of Pharmacology, Faculty of Pharmacy, University of Gezira, Wad Madani, Sudan.

DOI: 10.4236/health.2012.49103                

Abstract

Background: Development and maintenance of penile erection requires the relaxation of corpus cavernosum smooth muscle (CCSM) cells and it is essentially mediated by nitric oxide (NO). Pausinystalia yohimbe bark is traditionally used for the treatment of erectile dysfunction (ED). Objectives and Methods: This study aimed to evaluate the effects of the methanolic extract of P. yohimbe bark (10 mg/ml) on isolated rabbit corpus cavernosum smooth muscle (CCSM). Results: Methanolic extract of P. yohimbe bark blocked contractions in CCSM induced by adrenergic agonists, through facilitating NO release from the endothelial cells. Conclusion: The obtained results revealed that, methanolic extract of P. yohimbe bark caused relaxation of CCSM that validates its traditional aphrodisiac property, thus it could be used to initiate and maintain erection in cases of erectile dysfunction.

Keywords

P. yohimbe Bark; Corpus Cavernosum Relaxation; Nitric Oxide; Aphrodisiac; Erectile Dysfunction

Conflicts of Interest

The authors declare no conflicts of interest.

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