Abstract
Until recently, erectile dysfunction (ED) was treated by either sexual counseling or penile prosthesis implantation. The advent of intracavernous and transurethral agents has expanded the number of therapeutic options available to ED patients. Furthermore, the approval of oral sildenafil for the treatment of ED in 1998 has prompted an increased awareness of the disease process. With ED now amenable to pharmacologic solutions, research is continuously underway to elucidate the mechanisms underlying the pathophysiologic basis of ED. The hemodynamic changes associated with each erectile event require the integrity of the penile vasculature and neural pathways. Studies that scrutinize the pathophysiology of ED have revealed various modulators or agents that may play a significant role in penile erection. These agents have been demonstrated to mediate their effects through modulation with gap junctions and potassium channels. These findings are facilitated through studies on animal models, specifically aged and diabetes-induced rats. There also appears to be a central control of the cardiac, respiratory, and penile functions that ultimately effects penile tumescence via an intricate cascade of coordinated events. With investigators striving to shed light on the pathophysiologic process of ED, the future does look bright for ED patients as more therapeutic agents, such as new oral agents and gene therapy, are on the horizon.
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References
Hinman F, Jr.: Atlas of Urosurgical Anatomy. Philadelphia: WB Saunders Co.; 1993.
Melman A, Gingell JC: The epidemiology and pathophysiology of erectile dysfunction. J Urol 1999, 161: 5–11.
Melman A, Rehman J: Pathophysiology of erectile dysfunction. Molecular Urology 1999, 3: 87–102.
Christ G J, Brink PR, Melman A.: The role of gap junctions and ion channels in the modulation of electrical and chemical signals in human corpus cavernosum smooth muscle. Intl Impot 1993, 5: 77–96.
Christ G J, Brink PR: An analysis of the presence and physiological relevance of subconducting states of connexin43-derived gap junction channels in cultured human corporal vascular smooth muscle cells. Circ Res 1999, 84: 797–803.
Lagaud G, Davies KP, Venkateswarlu K, efThe physiology, pathophysiology and therapeutic potential of gap junctions in smooth muscle. Current Drug Targets 2002, 3: 1–14.
Christ G J: Gap junctions and ion channels: relevance to erectile dysfunction. Int J Impot 2000, 12: 515 - S25.
Venkateswarlu K, Giraldi A, Zhao W, et al Potassium channels and human corporeal smooth muscle cell tone: diabetes and relaxation of human corpus cavernosum smooth muscle by adenosine triphosphate sensitive potassium channel openers. J Urol 2002, 168:355–361.
Christ GJ: The penis as a vascular organ: the importance of corporal smooth muscle tone in the control of erection. Urol Clin North Am 1995, 22: 727–745.
Palmer LS, Valcic M, Melman A,: Characterization of cyclic AMP accumulation in cultured human corpus cavernosum smooth muscle cells. J Urol 1994, 152: 1308–1314.
Trigo-Rocha F, Hsu GL, Donatucci CF,: Intracellular mechanism of penile erection in monkeys. Neurol Urodynamics 1994, 13: 71–80.
Miller MA, Morgan RJ: Eicosanoids, erections, and erectile dysfunction. Prostaglandins Leukot Essent Fatty Acids 1994, 51: 1–9.
Pickard RS, Powell PH, Zar MA: Nitric oxide and cyclic GMP formation following relaxant nerve stimulation in isolated human corpus cavernosum. BrJ Urol 1995, 75: 516–522.
Cahn D, Melman A, Valcic M, Christ GJ: Forskolin: a promising new adjunct to intravenous pharmacotherapy. J Urol 1996, 155: 1789–1794.
Christ GJ, Moreno AP, Melman AP, Spray DC: Gap junction-mediated intercellular diffusion of Cat+ in cultured human corporal smooth muscle cells. Am J Physiol 1992, 263: C373 - C383.
Giraldi A, Wen YP, Geliebter J, et al Differential gap junction mRNA expression in human corpus cavernosum: a significant regulatory in cell-to-cell communication? [abstract] J Urol 1995, 153:508A.
Autieri MV, Melman A, Christ GJ: Identification of a down-regulated mRNA transcript in corpus cavernosum from diabetic patients with erectile dysfunction. Int.] Impot Res 1996, 8: 69–73.
Anderson KE: Pharmacology of lower urinary tract smooth muscle cells and penile erectile tissues. Pharmacol Rev 1993, 45: 253–309.
Fan SF, Brink PR, Melman A, Christ GJ: An analysis of the maxi-K+ (KCa) channel in cultured human corporal smooth muscle cells. J Urol 1995, 153: 818–825.
Kim N, Azadzoi KM, Goldstein I, Saenz de Tejada I: A nitric-oxidelike factor mediates nonadrenergic noncholinergic neurogenic relaxation of penile corpus cavernosum smooth muscle. J Clin Invest 1991, 88: 112–118.
Ignarro Li, Bush PA, Buga GM, et al Nitric oxide and cyclic GMP formation upon electric field stimulation cause relaxation of corpus cavernosum smooth muscle. Biochem Biophys Res Commun 1990, 170:843–850.
Rajfer J, Aronson WJ, Bush PA, et al Nitric oxide as a mediator of relaxation of the corpus cavernosum in response to nonadrenergic, noncholinergic neurotransmission. N Engl J Med 1992, 326:90–94.
Kirkeby HJ, Fahrenkrug J, Holmquist F, Ottesen B: Vasoactive intestinal polypeptide (VIP) and peptide histidine methionine (PHM) in human penile corpus cavernosum tissue and circumflex veins: localization and in vitro effects. EurJ Clin Invest 1992, 22: 24–30.
Adaikan PG, Ratnam SS: Pharmacology of penile erection in humans. Cardiovasc Intervent Radio 1988, 11: 191–194.
Roy JB, Petrone RL, Said SI: A clinical trial of intracavernous vasoactive intestinal peptide to induce penile erection. J Urol 1990, 143: 302–304.
Brindley GS: Pilot experiments on the actions of drugs injected into the human corpus cavernosum penis. BrJ Pharmacol 1986, 87: 495–500.
Loewy AD: Virus as transneuronal tracers for defining neural circuits. Neurosci Biobehav Rev 1998, 22: 679–684.
Hosogai M, Matsuo S, Sibahara T, et al Projection of respiratory neurons in rat medullary raphe nuclei to the phrenic nuclei. Respir Physiol 1998, 112:37–50.
Rampin O, Giuliano F: Central control of the cardiovascular and erection systems: possible mechanisms and interactions. Am J Cardiol 2000, 86: 19F - 22F.
De Groat WC, Steers W: Neuroanatomy and neurophysiology of penile erection. In Contemporary Management of Impotence and Infertility. Edited by Tanagho E, Lue TF, McClure D. Baltimore: Williams and Wilkins; 1988.
De Groat WC, Booth AM: Neural control of penile erection. In The Autonomic Nervous Control of the Urogenital System, vol 3. Edited by Maggi CA. London: Harwood Academic Publishers; 1993: 467–479.
Steers WD: Neural control of penile erection. Semin Urol 1990, 8: 66–79.
MacLean PD, Ploog DW: Cerebral representation of penile erection. J Neurophysiol 1962, 25: 29–55.
Wagner CK, Clemens LG: Projections of the paraventricular nucleus of the hypothalamus to the sexually dimorphic lumbosacral region of the spinal cord. Brain Res 1991, 539: 254.
Chen K, Chan SHH, Chang CLS, Chan JYH: Participation of paraventricular nucleus of hypothalamus in central regulation of penile erection in rat. J Urol 1997, 158: 238–244.
Murphy MR, Seckl JR, Burton S, et al.: Changes in oxytocin and vasopressin secretion during sexual activity in men. J Clin Endocrinol Metab 1987, 65:738–741.
Saenz DE Tejada I, Ware JC, Blanco R, et al.: Pathophysiology of prolonged erection associated with trazodone use. J Urol 1991, 145:60–64.
van Ahlen H, Peichota HJ, Kias HJ, et al.: Opiate antagonists in erectile dysfunction: a possible new treatment option? Results of a pilot study with naltrexone. Eur Urol 1995, 28:246–250.
Feldman HA, Goldstein I, Hatzichristou D G, et al.: Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol 1994, 151:54–61.
Hartmann U: Psychological subtypes of erectile dysfunction: result of statistical analysis and clinical practice. World J Urol 1997, 15: 56–64.
Comarr AE: Sexual function among patients with spinal cord injury. Urol Int 1970, 25: 134–168.
Leonard MP, Nickel CJ, Morales A: Hyperprolactinemia and impotence: why, when, and how to investigate. J Urol 1989, 142: 992–994.
Rehman J, Benet E, Melman A: Arteriogenic Erectile Dysfunction: Evaluation and Treatment. Mediguide to Urology, vol 8. Edited by Carson CC Ill. New York: Bayor Corp; 1996: 1–7.
LueTF: Male sexual dysfunction. In Smith’s General Urology, edn 14. Edited by Tanagho EA, McAninch JW: Norwalk, CT: Appleton and Lange; 1994: 776.
Rehman J, Chenven E, Brink PR, et al Diminished neurogenic but not pharmacological erections in the 2- to 3-month experimentally diabetic F-344 rat. Am J Physiol 1997,272:H1960–H1971.
Seftel AD: Erectile dysfunction in the elderly: epidemiology, etiology and approaches to treatment. J Urol 2003, 169: 1999–2007.
Christ G J, Rehman J, Day N, et al.: Intracorporal injection of hSlo cDNA in rats produces physiologically relevant alterations in penile function. Am J Physiol 1998, 275:H600–H608.
Melman A, Zhao W, Davies KP, et al The successful long-term treatment of age-related erectile dysfunction with hSlo cDNA in rats in vivo. J Urol 2003, 170:285–290.
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Leung, A.C., Christ, G.J., Melman, A. (2004). Physiology of Penile Erection and Pathophysiology of Erectile Dysfunction. In: Lue, T.F. (eds) Atlas of Male Sexual Dysfunction. Current Medicine Group, London. https://doi.org/10.1007/978-1-4613-1087-7_1
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