title: Intravital microscopy of the murine urinary bladder microcirculation.
abstract: OBJECTIVE
  To establish an in vivo mouse model of the urinary bladder microcirculation, and characterize the molecular mechanisms of endotoxin-induced leukocyte recruitment.
  
  
  METHODS
  The murine model was adapted from a technique previously reported for the rat. Mouse bladder microcirculation was observed using intravital microscopy, four hours after intravesical challenge with lipopolysaccharide (LPS) and leukocyte-endothelial interactions were examined. Molecular mechanisms of leukocyte recruitment were identified using antibodies to adhesion molecules and chemokines.
  
  
  RESULTS
  LPS from Escherichia coli administered intravesically resulted in a significant increase in leukocyte adhesion and rolling at four hours post stimulation. LPS from Pseudomonas aeruginosa administered at similar doses resulted in a significant, but lower increase in leukocyte adhesion after four hours compared with E. coli LPS. Leukocyte adhesion within the bladder microcirculation was dependent on α(4) -integrins and ICAM-1, whereas leukocyte rolling was P-selectin dependent, but α(4) -integrin independent. Blockade of MIP-2 and KC did not alter leukocyte-endothelial interactions. The bladder endothelium expressed P-selectin, ICAM-1, VCAM-1, MIP-2, and MCP-1. Only VCAM-1 endothelial expression was significantly increased after LPS stimulation.
  
  
  CONCLUSIONS
  The mouse model of the urinary bladder microcirculation is suitable for the study of inflammatory responses during urinary tract infection (UTI) in vivo.
authors.affiliation: Medical Sciences Graduate Program, McMaster University, Hamilton, ON, Canada.
authors.forename: Paulina M
authors.initials: PM
authors.lastname: Kowalewska
authors.forename: Lori L
authors.initials: LL
authors.lastname: Burrows
authors.forename: Alison E
authors.initials: AE
authors.lastname: Fox-Robichaud
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D015815:Cell Adhesion Molecules; D018925:Chemokines / Q000378:metabolism; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D004926:Escherichia coli / Q000378:metabolism; D004927:Escherichia coli Infections / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D036904:Leukocyte Rolling / Q000187:drug effects; D007962:Leukocytes / Q000378:metabolism* / Q000473:pathology; D008070:Lipopolysaccharides / Q000737:chemistry / Q000633:toxicity; D051379:Mice; D008833:Microcirculation / Q000187:drug effects; D011550:Pseudomonas aeruginosa / Q000737:chemistry; D051381:Rats; D001743:Urinary Bladder / Q000098:blood supply* / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D014552:Urinary Tract Infections / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology
chemical_list: D015815:Cell Adhesion Molecules; D018925:Chemokines; D008070:Lipopolysaccharides