Characterization of alpha-adrenoceptor subtypes in the corpus cavernosum of patients undergoing sex change surgery.


Journal Article

PURPOSE: To characterize the subtypes of alpha1- and alpha2-adrenoceptors in the human corpus cavernosum from patients undergoing sex change surgery. MATERIALS AND METHODS: Saturation and competition radioligand binding studies were performed for characterization at the protein level. Alpha1-adrenoceptors were labeled with [3H]prazosin and [3H]tamsulosin, while alpha2-adrenoceptors were labeled with [3H]RX 821002. Alpha1-adrenoceptor subtype mRNA was additionally determined by reverse-transcriptase polymerase chain reaction and RNase protection assays. RESULTS: Human corpus cavernosum expressed approximately 32 and approximately 22 fmol./mg. protein alpha1- and alpha2-adrenoceptors, respectively. Competition studies with the alpha1A-selective antagonists 5-methylurapidil and (+)-niguldipine and the alpha1D-selective BMY 7378 revealed a mixed alpha1A/alpha1B-adrenoceptor population with no evidence for alpha1D-adrenoceptor protein. In contrast alpha1D-adrenoceptors were readily detected at the mRNA level. Competition binding studies with the alpha2A-selective oxymetazoline and the alpha2B-selective prazosin and ARC 239 revealed a homogeneous population of alpha2A-adrenoceptors. CONCLUSIONS: We conclude that human corpus cavernosum expresses predominantly alpha1A-, alpha1B- and alpha2A-adrenoceptor protein; additionally the alpha1D-adrenoceptor is present at the mRNA level.

Full Text

Cited Authors

  • Goepel, M; Krege, S; Price, DT; Michelotti, GA; Schwinn, DA; Michel, MC

Published Date

  • November 1999

Published In

Volume / Issue

  • 162 / 5

Start / End Page

  • 1793 - 1799

PubMed ID

  • 10524937

Pubmed Central ID

  • 10524937

Electronic International Standard Serial Number (EISSN)

  • 1527-3792

International Standard Serial Number (ISSN)

  • 0022-5347

Digital Object Identifier (DOI)

  • 10.1097/00005392-199911000-00072


  • eng