title: Use of Fluorescein Isothiocyanate-Inulin as a Marker for Intestinal Ischemic Injury.
abstract: BACKGROUND
  Intestinal ischemia is observed in conditions such as mesenteric ischemia, or during traumatic events such as intestinal transplantation. Intestinal ischemia leads to pathophysiologic disruptions that present as increased fluid secretion into the intestinal lumen. We propose a novel method to detect real-time ischemic injury that is used in an in vitro model applicable to intestinal transplantation.
  
  
  METHODS
  Small intestine segments from rats were procured. The segments were attached to customized perfusion chambers. Both intestines were perfused on the vascular side with a Ringer buffer solution. The experimental buffer solution was bubbled with 100% nitrogen to mimic ischemia. Both lumens were perfused with 3 mL HEPES-Ringer solution containing 50 μM fluorescein isothiocyanate (FITC)-inulin. Intraluminal samples were collected at 15-minute intervals to measure FITC-inulin concentration using a nanofluorospectrophotometer. Intestinal tissue samples were processed and evaluated by a blinded pathologist using the Park/Chiu scoring system for grading intestinal ischemia.
  
  
  RESULTS
  Samples collected from the ischemic intestine showed a significant decrease in FITC-inulin fluorescence compared with the control intestine, indicating enhanced fluid secretion. Histopathologic samples from the experimental arm exhibited higher scores of ischemic injury in comparison with the control arm, confirming the FITC-inulin as a correlation to ischemia.
  
  
  CONCLUSIONS
  Fluorescein isothiocyanate-inulin can be used as a real-time volume marker to monitor the ischemic state of intestinal tissue. A positive correlation between the degree of fluid shift and presence of ischemic injury. The changes in fluorescence signal provide a potential selective method to measure real-time fluid changes inside an intestinal graft to evaluate viability.
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT.
authors.forename: Abedalrazaq
authors.initials: A
authors.lastname: AlKukhun
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Caturegli
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT.
authors.forename: Armando Salim
authors.initials: AS
authors.lastname: Munoz-Abraham
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT.
authors.forename: Sami
authors.initials: S
authors.lastname: Judeeba
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT.
authors.forename: Roger
authors.initials: R
authors.lastname: Patron-Lozano
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Morotti
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT.
authors.forename: Manuel I
authors.initials: MI
authors.lastname: Rodriguez-Davalos
authors.affiliation: Department of Surgery, Yale University School of Medicine, New Haven, CT. Electronic address: john.geibel@yale.edu.
authors.forename: John P
authors.initials: JP
authors.lastname: Geibel
mesh_terms: D000818:Animals; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives*; D007422:Intestines / Q000098:blood supply* / Q000000981:diagnostic imaging*; D007444:Inulin / Q000031:analogs & derivatives*; D007511:Ischemia / Q000000981:diagnostic imaging*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: C584353:FITC-inulin; D007444:Inulin; D016650:Fluorescein-5-isothiocyanate