Relaxant effects of an alkaloid-rich fraction from Aspidosperma ulei root bark on isolated rabbit corpus cavernosum

Campos, Adriana Rolim; Cunha, Karina M.A.; Santos, Flávia Almeida; Silveira, Edilberto R.; Uchôa, Daniel E. A.; Nascimento, Nilberto R.F.; Rao, V. S. N.

doi:10.1038/sj.ijir.3901624

Cited by 8 publications

(7 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Then it was immediately immersed in an organ chamber containing fresh 4 1C Krebs solution and the corpus cavernosum tissue was carefully dissected away from the surrounding tunica. 27,28 Three to four cavernosal strips of approximately equal size (2 Â 2 Â 8 mm) were obtained from each penis and were prepared for organ bath studies separately. Each cavernosal strip was tied with silk in one organ chamber with one end fixed to a tissue holder and the other secured to a force transducer.…”

Section: Cavernosal Tissue Strips Preparationmentioning

confidence: 99%

Chuanxiongzine relaxes isolated corpus cavernosum strips and raises intracavernous pressure in rabbits

et al. 2009

View full text Add to dashboard Cite

It has been shown that there are many Chinese traditional herbals that can enhance sexual activity. Chuanxiongzine is a vasoactive ingredient that has been isolated and purified from Ligusticum chuanxiong Hort. In previous studies, it has been found that chuanxiongzine was effective in relaxing rabbit corpus cavernosum smooth muscle. We determined the effects of chuanxiongzine on relaxation of isolated corpus cavernosum strips in vitro and on increase of intracavernous pressure (ICP) in vivo in rabbits. Chuanxiongzine caused a concentration-dependent relaxation of phenylephrine precontracted isolated corpus cavernosum strips (EC 50 1.58 Â 10 À4 mol l À1 ), which were endothelium independent and NO independent. However, the guanylyl cyclase inhibitor 1-H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one significantly shifted the chuanxiongzine concentration-response relationship to the right. Although there was no significant difference in the level of cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) in isolated corpus cavernosum strips treated with chuanxiongzine or vehicle, chuanxiongzine caused a significant rise in the level of cGMP and cAMP in isolated corpus cavernosum strips pretreated with the activator of adenylyl cyclase forskolin and the source of NO sodium nitroprusside. In an in vivo study, chuanxiongzine dose-dependently raised ICP after the intracavernous injection of its cumulative doses (0.5, 1, 2 and 5 mg kg À1 ). The ICP increased from baseline to 19.1±3.7, 24.8±2.1, 30.2 ± 4.8 and 39.7 ± 6.1 mm Hg, respectively, and the duration of tumescence ranged from 8.5 ± 2.8 to 22.9 ± 7.3 min. Our results show that chuanxiongzine can relax isolated corpus cavernosum strips of rabbits in vitro and increase ICP of rabbits in vivo, which is neither endothelium dependent nor NO dependent, but may be partly mediated by the inhibition of cAMP phosphodiesterase or cGMP phosphodiesterase.

show abstract

Section: Cavernosal Tissue Strips Preparationmentioning

confidence: 99%

Chuanxiongzine relaxes isolated corpus cavernosum strips and raises intracavernous pressure in rabbits

et al. 2009

View full text Add to dashboard Cite

show abstract

“…24 The current findings offer new perspectives on the mechanisms of yohimbine-induced relaxation. In spite of its long history in the treatment of erectile dysfunction, 4 little is known about the non-adrenergic, non-cholinergic pathways involved in yohimbine-induced relaxation, and controlled studies have only been undertaken for the past few years.…”

Section: Discussionmentioning

confidence: 75%

Yohimbine relaxes the human corpus cavernosum through a non-adrenergic mechanism involving the activation of K+ATP-dependent channels

et al. 2009

Self Cite

View full text Add to dashboard Cite

The mechanism by which yohimbine relaxes the human corpus cavernosum remains unclear. Using the human corpus cavernosum strips immersed in isometric baths containing Krebs-Henseleit solution, this study investigates the effect of yohimbine on the relaxation of the human corpus cavernosum through nitrergic pathways involving the activation of ATP-dependent potassium channels (K ATP ). The maximal relaxation induced by yohimbine in the human corpus cavernosum strips pre-contracted with phenylephrine was 100±0% and only 30.5±5.0% when they were precontracted with 60-mM potassium (K þ ) solution. The maximal relaxation induced by yohimbine in phenylephrine pre-contracted tissues was significantly inhibited by tetrodotoxin, 1H-[1,2,4] oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) or 7-nitroindazole (43.6, 36.1 and 42.6%, respectively). Neither the combination charybdotoxin-apamin nor tetraethylammonium altered the response of the human corpora cavernosa strips to yohimbine. Nevertheless, glibenclamide decreased the maximum relaxant response to yohimbine by 29.8% (Po0.05; n ¼ 12). The results suggest that yohimbine relaxes the human corpus cavernosum by a non-adrenergic, non-cholinergic mechanism, probably activating the nitrergic-soluble guanylate cyclase (NO-sGc) pathway and K ATP .

show abstract

“…Since several synthetic drugs commonly used in erectile dysfunction are associated with undesirable side effects, there is rising interest in discovering new effective drugs. Various reports on natural products with vasodilating effects on corpus cavernosum smooth muscle appeared recently [3, 4]. …”

Section: Introductionmentioning

confidence: 99%

Erectogenic Effects ofClerodendron capitatum: Involvement of Phosphodiesterase Type-5 Inhibition

Abdelwahab

Mohamed²,

Mohamed³

et al. 2012

Evidence-Based Complementary and Alternative Medicine

View full text Add to dashboard Cite

Clerodendron capitatum (Willd) (family: verbenaceae) is locally named as Gung and used traditionally to treat erectile dysfunction. Therefore, the current study was designed to investigate the erectogenic properties of C. capitatum. The relaxation effect of this plant was tested on phenylephrine precontracted rabbit corpus cavernosum smooth muscle (CCSM). The effects of C. capitatum were also examined on isolated Guinea pig atria alone, in the presence of calcium chloride (Ca2+ channel blocker), atropine (cholinergic blocker), and glibenclamide (ATP-sensitive K+ channel blocker). These effects were confirmed on isolated rabbit aortic strips. The extract, when tested colorimetrically for its inhibitory activities on phosphordiesterase-5 (PDE-5) in vitro towards p-nitrophenyl phenyl phosphate (PNPPP), was observed to induce significant dose-dependent inhibition of PDE-5, with an ID50 of 0.161 mg/ml (P < .05). In conclusion, our results suggest that C. capitatum possesses a relaxant effect on CCSM, which is attributable to the inhibition of PDE-5, but not mediated by the release calcium, activation of adrenergic or cholinergic receptors, or the activation of potassium channels.

show abstract

Relaxant effects of an alkaloid-rich fraction from Aspidosperma ulei root bark on isolated rabbit corpus cavernosum

Cited by 8 publications

References 35 publications

Chuanxiongzine relaxes isolated corpus cavernosum strips and raises intracavernous pressure in rabbits

Chuanxiongzine relaxes isolated corpus cavernosum strips and raises intracavernous pressure in rabbits

Yohimbine relaxes the human corpus cavernosum through a non-adrenergic mechanism involving the activation of K+ATP-dependent channels

Erectogenic Effects ofClerodendron capitatum: Involvement of Phosphodiesterase Type-5 Inhibition

Contact Info

Product

Resources

About