Læknablaðið - 15.09.1993, Page 45

LÆKNABLAÐIÐ 1993; 79: 295-6
295
NÝR DOKTOR í LÆKNISFRÆÐI
GUÐJÓN HARALDSSON
Þann 29. janúar 1993 varði Guðjón
Haraldsson læknir doktorsritgerð við
háskólann í Gautaborg. Ritgerðin nefnist á
frummáli: »RadicctI production after warm
ischaemia. An experimental study in rabhit
kidneys«. Fer ágripið hér á eftir.
During the last two decades research has
shown that radicals are involved in many
pathological conditions and the list of diseases
where radicals may be involved is constantly
growing. Formation of radicals is also a
problem in preservation of renal function
in conservative renal surgery and in renal
transplantation. Earlier studies have used
indirect methods for the evaluation of radical
production and radical damage but with
the evolution of electron spin resonance
(ESR) and spin trapping a direct method for
detecting radicals in biological systems has
emerged.
Aims of the study:
1. To study radical production at reperfusion
after ischaemia in the rabbit kidney by
using the spin trap technique.
2. To study how the radical production is
influenced by intervention against radicals.
3. To study effects of intervention against
radicals on kidney function after 60 min of
ischaemia.
Methods: New Zealand white rabbits were
used as experimental animals. In the acute
experiments where radical production was
studied the aorta and caval vein were ligated
below the level of the left renal artery and
vein. A plastic cannula was placed in the aorta
with the tip close to the left renal artery for
infusion of the spin trap (OXANOH). When
exposed to radicals OXANOH is oxidized
to the stable form OXANO*. The blood
Key words: Rabbit kidney, ischaemia-reperfusion, kidney
function, spin trap, OXANOH, ESR, oxypurinol, IC-SOD,
EC-SOD, heparin, desferrioxamine, mannitol.
flow in the left renal artery was measured by
ultrasound technique. Blood samples were
withdrawn from the left renal vein for analysis
of OXANO* content. OXANO* concentration
was determined by ESR. Measurements of
radical production were performed before
and after 60 min of ischaemia without
pretreatment or after pretreatment with either
oxypurinol, IC-SOD, EC-SOD, heparin,
mannitol or desferrioxamine. The effects of
pretreatment with these substances on kidney
function were studied chronically. On the first
day a rightsided nephrectomy was performed
and the left kidney subjected to 60 min of
ischaemia with or without pretreatment. After
two days the animals were re-anaesthetized
and the glomerular and tubular functions
determined.
Results: After 2 min of infusion of the spin