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Contraction mechanism, human aortic smooth muscle cell, sildenafil


Erectile dysfunction is defined as the inability to gain and/or maintain a penile erection sufficient for satisfactory sexual performance. Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor used in the treatment of erectile dysfunction. The aim of this study is to investigate the effect of sildenafil (0.8% in cell media) on the mechanism of human aortic smooth muscle contraction. Human smooth muscle cells treated with sildenafil for 1 and 4 days. These cells were then homogenized, and enzymes and proteins responsible for the mechanism of intracellular contraction were analysed. Rho-kinase (ROCK) activity, RhoA, ROCK II, CPI-17α, PDE5a, and PLC levels were evaluated by using ELISA. In this study, it was observed that sildenafil increased RhoA, PDE5a and CPI-17α levels, and decreased ROCK enzyme activity.


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How to Cite

Alp, H., Tutun, H., Şingirik, E., Kaplan, H. M., Kaya, M. M., & Altıntaş, L. (2022). DETERMINATION OF THE EFFECTIVENESS OF SILDENAFIL ON HUMAN AORTIC SMOOTH MUSCLE CELLS. Journal of Applied Biological Sciences, 16(2), 266–273. Retrieved from




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