Objectives: Sildenafil citrate (Viagra) is widely used as an aphrodisiac drug and for the treatment of erectile dysfunction. The present study was planned to study the morphological changes that might occur in the frontal cortex of the adult rat in response to chronic intake of Viagra and discover whether these changes are reversible or irreversible. Material and Methods: Forty adult male rats were used where they were classified into three groups: A control group (10 rats), B experimental treated group (20 rats), and C recovery group (10 rats). The treated and recovery groups received therapeutic dose of Viagra for 30 days. The control and the treated group were sacrificed at the first day after the designated period (30 days), the recovery group was sacrificed two weeks after the end of experiment. Results: The pyramidal cell neurons are little in number; some of them are atrophic, degenerated. Their cytoplasm showed varied degree of cellular degenerative changes with vaculation of their myelinated axons. Pyramidal neurons of recovery animals showed nearly complete recovery. Conclusion: Chronic intake of Viagra produced reversible morphological changes in pyramidal neurons of the frontal cortex of adult male rats.
Wanda, M. and Cohn, G. (1991) Handbook of Toxicological Pathology. Academic Press, Sydney, New York, 625-674.
Boolell, U.M., Alle, M., Ballard, G., Nayalor, A. and Gigll, C. (1996) Oral Sildenafil: An Orally Active Type GMPS for Treatment of Penile Erectile Dysfunction. International Journal of Impotence Research, 8, 47-52.
Benchkroun, A., Faik, M. and Benjelloun, S. (2003) A Baseline-Controlled Open-Label Study to Assess the Safety and Efficacy of Sildenafil Citrate (Viagra) in Patients with Erectile Dysfunction. International Journal of Impotence Research, 1, 519-524. https://doi.org/10.1038/sj.ijir.3900969
Wellis, R., Corbin, J., Francis, S. and Ellis, P. (1999) Tissue Distribution of Phosphodiesterese Families and the Effect of Sildenafil on Tissue in Vitro. American Journal of Cardiology, 83, 3c-12c. https://doi.org/10.1016/S0002-9149(99)00042-9
Giorgi, M., Squitti, R., Bonsi, P. and Toschi, G. (1994) Activities of 3,5, Cyclic Nucleotide Phosphodiesterase in the Superior Cervical Ganglion in Rats. Neurochemistry International, 25, 493-500. https://doi.org/10.1016/0197-0186(94)90026-4
Giordano, D., Desterani, M., Citro, G. and Giorgy, H. (2001) Expression of CGMP-Specific PDES in Mouse Tissue. Biochimica et Biophysica Acta, 1539, 16-27. https://doi.org/10.1016/S0167-4889(01)00086-6
Basu, A. and Ryder, R. (2004) New Treatment Option for Erectile Dysfunction in Patients with D.M. Drug, 69, 2667-2688. https://doi.org/10.2165/00003495-200464230-00004
Feldman, R.M., Meuleman, E. and Strees, W. (1999) Sildenafil Citrate in the Treatment of Erectile Dysfunction. International Journal of Clinical Practice, 53, 10-12.
Deforge, D., Blakman, J. and Gamtty, C. (2006) Male Erectile Dysfunction Following Spinal Cord Injury. Spinal Cord, 44, 465-473. https://doi.org/10.1038/sj.sc.3101880
Aviv, A., Shelef, A. and Weizeman, A. (2004) An Open-Label Trial of Sildenafil Treatment in Male Schizophrenia Patients with Erectile Dysfunction. Journal of Clinical Psychiatry, 65, 96-103. https://doi.org/10.4088/JCP.v65n0117
Gopalakrishnan, R., Jakob, K. and Kuruvilla, A. (2006) Sildenafil in Treatment of Antipsychotic-Induced Erectile Dysfunction. American Journal of Psychiatry, 163, 494-499. https://doi.org/10.1176/appi.ajp.163.3.494
FDA (2015) Viagra-Sildenafil Citrate Tablet, Film Coated: Full Prescribing Information. http://labeling.pfizer.com/ShowLabeling.aspx?id=652
Eweka, A.O. and Eweka, A.B. (2011) The Effect of Sidenafil Citrate on the Medial Geneculate Body of Adult Rat. Journal of Cell and Animal Biology, 5, 56-60.
Palay, S. and Chan-Palay, L. (1974) Technique of Electron Microscope. In: Cytology and Organization, Springer Verlag, Berlin, Chap. 8, 105-132.
Hayat, N. (1986) Basic Technique for Transmission Electron Microscope. Academic Press, Cambridge, 1-20. https://doi.org/10.1016/B978-0-12-333926-3.50004-X
Tharakan, B. and Banyaw, B. (2005) Potential Therapy in Sexual Dysfunction. Physical Therapy Research, 19, 457-463. https://doi.org/10.1002/ptr.1634
McMahan, C., Samali, R. and Johson, H. (2000) Efficacy Safety and Patient Acceptance of Sildenafil Citrate as Treatment of Erectile Dysfunction. Journal of Urology, 164, 1192-1196. https://doi.org/10.1016/S0022-5347(05)67139-X
Eardley, I. (2001) Efficacy and Safety of Seldenafil Citrate in the Treatment of Men with Erectile Dysfunction. The British Journal of Psychiatry, 178, 325-330. https://doi.org/10.1192/bjp.178.4.325
Abdel-Naser, M., Iman, A. and Wollena, U. (2004) Sildenafil Citrate Significantly Improves Nocturnal Penile Erection in Sildenafil Nonresponding Patients with Psychogenic Erectile Dysfunction. International Journal of Impotence Research, 16, 552-556. https://doi.org/10.1038/sj.ijir.3901245
Cheitlin, M., Hutter, A., Brindis, R., Gars, P. and Kaul, S. (1999) The Use of Sildanafil Citrate (Viagra) in Patients with Cardiovascular Disease. Circulation Journal, 99, 168-177. https://doi.org/10.1161/01.CIR.99.1.168
Gali, N., Ghofrani, H., et al. (2005) Sidanafil Citrate Therapy for Pulmonary Arterial Hypertention. The New England Journal of Medicine, 353, 2148-2157. https://doi.org/10.1056/NEJMoa050010
Hoeper, M., Welt, T., Izbicki and Rubin, L. (2006) Sidanafil Citrate Therapy for Pulmonary Arterial Hypertention. The New England Journal of Medicine, 354, 1019-1093. https://doi.org/10.1056/NEJMc053442
Cunningham, A.V. and Smith, K.H. (2001) Anterior Ischemic Optic Neurobathy Associated with Viagra. Journal of Neuro-Ophthalmology, 21, 22-25. https://doi.org/10.1097/00041327-200103000-00006
Pipia, M.R., Camardo, L. and Camardo, R. (2001) Intracranial Hemorrhage Associated with Sildenafil Citrate. Journal of Neurology, 248, 141-142. https://doi.org/10.1007/s004150170250
Pomeranz, H., Smith, K., Hart, W. and Egan, R. (2002) Sildenafil-Associated Non-Arterial Anterior Ischemic Optic Neuropathy. Ophthalmology, 109, 584-587. https://doi.org/10.1016/S0161-6420(01)00976-9
Pomeranz, H. and Bhavzsar, A. (2005) Non Arterial Ischemic Optic Neuropathy Is Developing Soon after Use of Sildenafil Citrate (Viagra). Journal of Neuro-Ophthalmology, 25, 9-13. https://doi.org/10.1097/00041327-200503000-00003
Farooq, M., Naravetlo, B., Moor, P. and Gupta, R. (2008) Role of Sildenafil Citrate in Neurological Disorder. Clinical Neuropharmacology, 31, 535-562. https://doi.org/10.1097/WNF.0b013e31815cd94c
Eweka, A.O. and Eweka, A.B. (2010) The Effect of Sidenafil Citrate on the Superior Colliculus of Adult Rat. Biology and Medicine, 2, 24-29.
Lorberboyn, M., Mena, I., Wainnstem, J., Boes, M. and Laml, Y. (2009) Effect of Sildenafil Citrate (Viagra) on Cerebral Blood Flow in Patients with Cerebro-Vascular Risk Factors. Acta Neurologica Scandinavica, 121, 370-376. https://doi.org/10.1111/j.1600-0404.2009.01307.x
Reinhard, M., Bolh, M.B. and Guschl bouer, B. (2005) Dynamic Cerebral Autoregulation in Acute Ischemic Stroke Assessed from Spontaneous Blood Pressure Fluctuation. Stroke, 36, 1691-1696. https://doi.org/10.1161/01.STR.0000173183.36331.ee
Haubrich, C., Kruska, W., Diehl, R. and Kloetzsch, C. (2003) Dynamic Autoregulation Testing in Middle Cerebral Artery Stenosis. Stroke, 34, 1881-1885. https://doi.org/10.1161/01.STR.0000080936.36601.34
Carey, B., Eames, P., Blake, M. and Potter, J. (2000) Dynamic Cerebral Autoregulation Is Unaffected by Aging. Stroke, 31, 2895-2900. https://doi.org/10.1161/01.STR.31.12.2895
Morgan, J., Alhatou, M., Oberlies, J. and Johuston, K. (2001) Transient Ischemic Attack and Stroke Associated with Soildensafil Use. Neurology, 57, 1730-1731. https://doi.org/10.1212/WNL.57.9.1730
Saritz, S. and Caplan, L. (2002) Transient Global Amnesia after Sildenafil Use. Neurology, 57, 778. https://doi.org/10.1212/WNL.59.5.778