Mechanisms of direct relaxant effect of sildenafil, tadalafil and vardenafil on corpus cavernosum.

@article{Lau2006MechanismsOD,
  title={Mechanisms of direct relaxant effect of sildenafil, tadalafil and vardenafil on corpus cavernosum.},
  author={L. Lau and P. Adaikan},
  journal={European journal of pharmacology},
  year={2006},
  volume={541 3},
  pages={
          184-90
        }
}
  • L. Lau, P. Adaikan
  • Published 2006
  • Chemistry, Medicine
  • European journal of pharmacology
Sildenafil, tadalafil, vardenafil and verapamil induced concentration-dependent relaxation of the rabbit corpus cavernosum muscle precontracted with noradrenaline. The maximal relaxation (%) at 20 microM was 61.4 +/- 6.9, 32.4 +/- 5.4, 100.0 +/- 5.5 and 86.6 +/- 5.1 (n = 5 each) respectively. Pre-incubation of cavernosal muscle strips with N(omega)-nitro-L-arginine or guanylate cyclase inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) but not adenylate cyclase inhibitor, cis-N-[2… Expand
Comparative relaxing effects of sildenafil, vardenafil, and tadalafil in human corpus cavernosum: contribution of endogenous nitric oxide release.
TLDR
The findings have shown that sildenafil, vardenafils, and tadalafil relax HCC tissues in a concentration-dependent manner, but the maximal relaxation obtained with tadalAFil was significantly lower than that obtained with sildanafil andvardenafil. Expand
Effect of sildenafil and rolipram on adrenergic responses in isolated human and monkey corpus cavernosum.
TLDR
Sildenafil and rolipram induced concentration-dependent reversal of human and monkey CC tone mediated by NA and underline the importance of the cyclic adenosine monophosphate-dependent signalling pathway in regulating the tone. Expand
Mechanisms of the relaxant effect of vardenafil in rat penile arteries.
TLDR
Vardenafil was the most potent of the four PDE inhibitors tested that maximally relaxed penile arteries, pD2 and maximum relaxation being 6.96+/-0.08 and 97+/-1% (n=48), respectively. Expand
Combination of alfuzosin and tadalafil exerts in vitro an additive relaxant effect on human corpus cavernosum.
TLDR
In vitro, the combination of alfuzosin and tadalafil is more efficient than each compound alone to relax adrenergic tone or to enhance nitrergic relaxation of the human corpus cavernosum. Expand
Different effects of different phosphodiesterase type-5 inhibitors in pre-eclampsia.
TLDR
Vardenafil seems to relax human umbilical artery stronger than sildenafil in both pre-eclamptic and normal pregnancies, and data indicate that vardenafils might affect vascular responsiveness of human umbILical artery through the involvement of NO/cGMP-dependent and independent pathways while sildanafil-induced responses were seemed to be completely No/cgMP- dependent. Expand
EFFECT OF THE PHOSPHODIESTERASE 5 INHIBITORS SILDENAFIL, TADALAFIL AND VARDENAFIL ON RAT ANOCOCCYGEUS MUSCLE: FUNCTIONAL AND BIOCHEMICAL ASPECTS
TLDR
PDE5 inhibitors enhance exogenous and endogenous nitric oxide‐mediated relaxation in the rat anococcygeus muscle and were more potent in preventing cGMP degradation in vitro than sildenafil and tadalafil. Expand
In vitro effects of PDE5 inhibitors sildenafil, vardenafil and tadalafil on isolated human ureteral smooth muscle: a basic research approach
TLDR
The results indicate that PDE5 inhibitors can reverse the tension of isolated human ureteral smooth muscle via cGMP-mediated pathways. Expand
Combination of doxazosin and sildenafil exerts an additive relaxing effect compared with each compound alone on human cavernosal and prostatic tissue.
TLDR
Sildenafil and doxazosin reduced adrenergic tone of prostatic and cavernosal smooth muscle and their combination provided a significant benefit when targeting relaxation of both tissues. Expand
Silodosin and tadalafil have synergistic inhibitory effects on nerve-mediated contractions of human and rat isolated prostates.
TLDR
The clinical application of a combination of an α1A-adrenoceptor antagonist and a phosphodiesterase 5 inhibitor for symptomatic BPH is supported and suggests that the drug combination requires endogenous nerve-activity for optimal effect. Expand
Examination of the effects of different phosphodiesterase type 5 enzyme inhibitors on the isolated rat myometrium contraction
The present study aims to explore the effects of the phosphodiesterase inhibitors tadalafil and vardenafil on the spontaneous contractions of isolated rat myometrium.The study included 45 virginExpand
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The data support the proposal that enhancement of penile erection by sildenafil in patients with erectile dysfunction involves potentiation of the NO-stimulated cGMP signal mediating relaxation of cavernosal smooth muscle during sexual stimulation. Expand
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