UNIVERSIDAD COMPLUTENSE DE MADRID FACULTAD DE ...

8 SUMMARY
8. SUMMARY
Introduction
The ischaemia in different organs is involved in a wide variety of human and
animal pathological processes, being common cause of death in the westem world.
Paradoxically, the relief of the ischaemic status by means of the reperfusión can
increase the damage.
Ihe purpose ofthis work is to study in experimental New Zeland rabbits, the acute
ischaemia of the artery mesenteric cranealis, the quantification of te lipid peroxidation
occasioned by oxygen free radicals (RLO) during the repermeabilización phase, and te
therapeutic effectiveness of superoxide dismutase (SOD). Ihe specific objectives looked
are:
• Developing an adequate experimental technique of production of acute ischaemia
in intestinal region in te rabbit by surgical obstruction ofte arteria mesenteric
cranealis (AMC), followed by a period of reperfusión.
• Performing with tli.is model a study of survival at different times of isehaemia
(sham, 15, 30, 60 and 120 minutes), establishing the time in which an approximate
rate of 50% of mortality takes place.
• Vaulting te tisular damage caused by te ischaemia - reperfusión on te intestinal
territory in-igated by this artery, studying te morphologic alterations taken place in
te different times.
• Determining te degree oflipid peroxidation tat take place in te small bowel as a
consequence ofthis isehaemia-reperfusión, vaulting te production of oxygen free
radicals (RLO) with the test ofte thiobarbituric acid (TBA).
• Checking te therapeutic effect over te ischaeniia lesions of antioxidative
substances like Zn-superoxide-dismutase over te lipid peroxidation, vaulting te
modifications on te survival rates, te production of oxygen free radicals in te
organs and morphologic and functional changes.
Material and method
The study was carried out in the surgical rooms and animal experimentation
facilities of the Service of Experimental Medicine and Surgery, in the Military Central
Hospital Gómez Ulla, in Madrid.
165 animals were used distributed in 11 series. For the study of survival, 5 series
of20 rabbits each one were employed and subjected at 0, 15, 30, 60 and 120 minutes of
ischaemia respectively, letting later a free repermeabilization. For the clinical assay of
survival wit SOD, two series of 10 animals were used, being subjected to 60 minutes
of ischemia, and applying in one of them a preventive therapy of SOD and in the other
one, used as control, physiologic salme solution. Finally, three series of 15 animals werc
used to evaluate the basal levels of MDA, one of them as a control in non ischemic
animals and oter two subjected to 60 minutes of ischemia, treated with SOD or
physiologíc salme solution respectively.
The anaesthesia was induced wit an endonasal mixture of ketamine and xilazine
and maintained with oxygen and nitrogen protoxide gas mixture, in which isofluorano
were vaporised, through of an anaesthesia equipment Boyle.
The surgical operations were performed in an experimental surgical room with
habitual equipment. employing a estándar box of abdominal surgery, added of a specific
material as a dissection clamp, vessel-loop rubber strips, and a microclamp of plastic
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