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POTASSIUM OUTWARD CURRENTS IN FRESHLY DISSOCIATED RABBIT CORPUS CAVERNOSUM MYOCYTES

2001; Lippincott Williams & Wilkins; Volume: 166; Issue: 3 Linguagem: Inglês

10.1016/s0022-5347(05)65940-x

1527-3792

John Malysz, Simon J. Gibbons, Steven Miller, Matthew T. Gettman, Ajay Nehra, Joseph H. Szurszewski, Gianrico Farrugia,

Pain Mechanisms and Treatments

No AccessJournal of UrologyINVESTIGATIVE UROLOGY1 Sep 2001POTASSIUM OUTWARD CURRENTS IN FRESHLY DISSOCIATED RABBIT CORPUS CAVERNOSUM MYOCYTES JOHN MALYSZ, SIMON J. GIBBONS, STEVEN M. MILLER, MATTHEW GETTMAN, AJAY NEHRA, JOSEPH H. SZURSZEWSKI, and GIANRICO FARRUGIA JOHN MALYSZJOHN MALYSZ , SIMON J. GIBBONSSIMON J. GIBBONS , STEVEN M. MILLERSTEVEN M. MILLER , MATTHEW GETTMANMATTHEW GETTMAN , AJAY NEHRAAJAY NEHRA , JOSEPH H. SZURSZEWSKIJOSEPH H. SZURSZEWSKI , and GIANRICO FARRUGIAGIANRICO FARRUGIA View All Author Informationhttps://doi.org/10.1016/S0022-5347(05)65940-XAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: Cavernous smooth muscle cells have a key role in the control of penile erection and detumescence. In this study the types of smooth muscle cells and currents present in isolated rabbit corpus cavernosum myocytes were characterized. Materials and Methods: Immunohistochemical methods were used to identify cavernous smooth muscle cells. Currents were recorded from freshly dissociated myocytes using the whole cell and amphotericin perforated patch clamp techniques. Results: Cavernous myocytes were identified by α-smooth muscle actin and smooth muscle myosin immunoreactivity. Based on electrical properties at least 2 types of myocytes were present. Type I cells showed more depolarized membrane potentials, lower capacitance, higher input resistance and increased current densities at positive potentials than type II cells. In types I and II cells at voltages positive to 30 mV, maxi K+ channel (Ca2+ activated large conductance K+ channel or BK) blockade with iberiotoxin or charybdotoxin reduced outward currents by approximately 40% to 80% at 80 mV. Maxi K+ channel blocking did not affect cell membrane potential. 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Volume 166Issue 3September 2001Page: 1167-1177 Advertisement Copyright & Permissions© 2001 by American Urological Association, Inc.Keywordspeniselectric stimulationpenile erectionmuscle, smoothrabbitsMetrics Author Information JOHN MALYSZ More articles by this author SIMON J. GIBBONS More articles by this author STEVEN M. MILLER More articles by this author MATTHEW GETTMAN More articles by this author AJAY NEHRA More articles by this author JOSEPH H. SZURSZEWSKI More articles by this author GIANRICO FARRUGIA More articles by this author Expand All Advertisement PDF downloadLoading ...