Keywords:
Small bowel, Emergency, MR, Experimental investigations, Diagnostic procedure, Ischaemia / Infarction
Authors:
D. Berritto, F. Iacobellis, F. Somma, M. P. Belfiore, S. Cappabianca, A. Rotondo, R. Grassi; Naples/IT
DOI:
10.1594/ecr2012/C-2152
Methods and Materials
After midline laparotomy,
in each rat a silk thread 3/0 was used to bind a loop around the superior mesenteric artery (SMA) (Group 1 and Group 3) or vein (SMV) (Group 2),
not jettightingthe loop.
The tips of the thread were brought into a silicon pipe and,
through it,
carried out to the back of the animal,
between its shoulders.
The thread tips were fixed to the pipe using medical plaster.
Muscles and skin were closed in two layers using aVicryl2/0 thread.
10 mg/Kg ofBaytril10% (Enrofloxacin2,5%,
Bayer AG,
Leverkusen,
Germany) was topically applied to the wounds to prevent infections.
The animals were returned to their cages after awakening,
and water and food were allowedad libitum.
Three days after surgery,
rats underwent a second anesthesia according to the same drug protocol,
and mesenteric ischemia was induced by pulling the threads out of the pipe.
In this way,
the loop around the SMV or SMA got squeezed and the arterial inflow through this artery was stopped.
In Group 3 rats SMA ligation was removed after 1 hour cutting the thread and the following reperfusion was macroscopically monitored until 7 hours.
In two rats of each group,
the bowel and the mesentery were exposed out of the abdominal cavity and macroscopic monitoring of externalized bowel was performed (Nikon Coolpix S210,
8.0 Megapixels of resolution,
ISO 2000,
Japan) until 8 hours.
In others two rats of each group Animals were monitored with 7Tesla Magnetic Resonance scanner (BioSpec70/16US,
BrukerMedical Systems,
Ettlingen,
Germany) at predetermined time points.
In rats of Group 1 and Group 2,
ischemic bowel was monitored until 8 hour; in Group 3 the SMA ligation was removed after 1 hour cutting the thread fixed on the back of the animal and the following reperfusion was monitored until 8 hours.
The bowel was removed for histological analysis at the end of observation (Fig.
1).