title: Rho kinase-related proteins in human vaginal arteries: an immunohistochemical and functional study.
abstract: BACKGROUND
  The calcium-sensitizing Rho A/Rho kinase pathway has been suggested to play a role in the control of nongenital vascular smooth muscle. Rho-associated kinases (ROKs) cause calcium-independent modulation of smooth muscle contraction, and have been demonstrated in the bladder, prostate, and corpus cavernosum. Until now, it is not known whether ROKs and related proteins play a role in the control of vaginal blood flow.
  
  
  OBJECTIVE
  To investigate by means of functional studies and immunohistochemistry the significance of the Rho pathway in human vaginal arteries.
  
  
  METHODS
  Vaginal tissue was obtained from five postmenopausal women. Specimens were processed for immunohistochemistry for ROK1, ROK2, RhoA, and RhoGDI. Segments of sub-epithelial vaginal arteries were mounted in a tissue bath. Effects of Y27632 on the concentration-response curves to phenylephrine (Phe) or Phe-precontracted preparations were investigated.
  
  
  METHODS
  The expression of Rho kinases ROK1, ROK2, and the Rho-associated protein RhoGDI in human vaginal arteries was investigated by means of immunohistochemistry. Tissue bath studies were conducted in order to characterize the effects of the ROK inhibitor Y27632 on isolated vaginal arteries.
  
  
  RESULTS
  A meshwork of α-actin immunoreactive arterioles was located in the sub-epithelium of human vaginal specimens. Immunoreactivities for ROK1, ROK2, RhoA, and RhoGDI were expressed in the smooth musculature of these arteries. At 0.1 and 1 µM Y27632, the contraction to Phe (10 µM) was 99 ± 17% and 28 ± 12% that of 124 mM K(+) . In Phe-contracted preparations, Y27632 produced relaxant responses.
  
  
  CONCLUSIONS
  The activation of alpha(1) -adrenoceptors contracts sub-epithelial human vaginal arteries via ROK-sensitive mechanisms. A role for these signals in the regulation of vaginal blood flow might be considered.
authors.affiliation: Hannover Medical School, Division of Surgery, Dept. of Urology & Urological Oncology, Hannover, Germany. sue_de_99@yahoo.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Ückert
authors.forename: Eginhard S
authors.initials: ES
authors.lastname: Waldkirch
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kauffels
authors.forename: Markus A
authors.initials: MA
authors.lastname: Kuczyk
authors.forename: Petter
authors.initials: P
authors.lastname: Hedlund
mesh_terms: D000577:Amides / Q000494:pharmacology; D001158:Arteries / Q000033:anatomy & histology / Q000201:enzymology*; D001160:Arterioles / Q000033:anatomy & histology / Q000201:enzymology; D005260:Female; D006801:Humans; D008875:Middle Aged; D010656:Phenylephrine / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D014621:Vagina / Q000033:anatomy & histology / Q000098:blood supply* / Q000201:enzymology / Q000502:physiology; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism* / Q000502:physiology
chemical_list: D000577:Amides; D011725:Pyridines; C108830:Y 27632; D010656:Phenylephrine; D054460:rho-Associated Kinases