Naunyn-Schmiedeberg's Archives of Pharmacology

, Volume 377, Issue 4, pp 473–481

Expression and functional role of β-adrenoceptors in the human urinary bladder urothelium

  • Atsushi Otsuka
  • Hitoshi Shinbo
  • Rikiya Matsumoto
  • Yutaka Kurita
  • Seiichiro Ozono
Original Article

DOI: 10.1007/s00210-008-0274-y

Cite this article as:
Otsuka, A., Shinbo, H., Matsumoto, R. et al. Naunyn-Schmied Arch Pharmacol (2008) 377: 473. doi:10.1007/s00210-008-0274-y

Abstract

We investigated the presence of β-adrenoceptor subtypes in human urinary bladder urothelium and examined whether β-adrenoceptors in the urothelium modulate the relaxation responses of isolated human detrusor strips to a β-adrenoceptor agonist. Expression of β1-, β2-, and β3-adrenoceptor mRNA in urothelium and detrusor smooth muscle was determined by reverse transcription-polymerase chain reaction, and the distribution of β1-, β2-, and β3-adrenoceptors in human urinary bladder urothelium were examined by immunohistochemistry. Paired human longitudinal detrusor strips with and without an intact urothelium were suspended in organ baths to construct concentration-response curves to isoproterenol. The possible involvement of urothelium-derived nitric oxide (NO) in this response was examined in additional experiments with urothelium-intact strips in the presence of NG-nitro-L-arginine methylester (L-NAME). Results confirmed the expression of β1-, β2-, and β3-adrenoceptors in the human urinary bladder urothelium. Further, the presence of the urothelium caused a parallel rightward shift of the concentration-response curve to isoproterenol with a significant reduction in potency (pEC50). L-NAME failed to exert any significant effect on the relaxation response to isoproterenol in the urothelium-intact strips. These results confirm the presence of β1-, β2-, and β3-adrenoceptors in human urinary bladder urothelium. Further, they suggest that urothelial β-adrenoceptors induce the release of a urothelium-derived factor which inhibits the β-adrenoceptor agonist-induced relaxation of the human detrusor smooth muscle and that this inhibitory mechanism might not involve NO.

Keywords

Human urotheliumβ-Adrenoceptor agonistMucosaβ3-AdrenoceptorBladderNitric oxide

Abbreviations

RT–PCR

reverse transcription-polymerase chain reaction

L-NAME

NG-nitro-L-arginine methyl ester

NO

nitric oxide

pEC50

potency, negative logarithm of the concentration giving half-maximal effect

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Atsushi Otsuka
    • 1
  • Hitoshi Shinbo
    • 1
  • Rikiya Matsumoto
    • 1
  • Yutaka Kurita
    • 1
  • Seiichiro Ozono
    • 1
  1. 1.Department of UrologyHamamatsu University School of MedicineHigashi-ku, HamamatsuJapan