Compensatory renal growth and mitochondrial function: the influence of warm ischemia and reperfusion.
OBJECTIVE
To evaluate the influence of ischemia/reperfusion injury on renal compensatory growth (CGR) and mitochondrial function.


METHODS
Forty five Wistar rats were divided in 3 groups: Control Group (GC) - 21 rats were submitted to a sham laparotomy and sacrificed at 1st (6 rats) and 7th (15 rats) postoperative days to evaluate the dry weight of both kidneys and their growth during 1 week (6 rats) and to quantify mitochondrial respiration (9 rats); Group 1 (G1) - 12 rats underwent right nephrectomy and were sacrificed 7 days later for analysis of renal mitochondrial function (6 rats) and dry weight (6 rats). Group 2 (G2) - renal warm ischemia for 60 minutes followed by right nephrectomy was performed in 12 rats; they were sacrificed 7 days later to evaluate renal mitochondrial function (6 rats) and dry weight (6 rats).


RESULTS
Dry weight (mg) of left kidneys at 7th day: GC - 219+/-18, G1 - 281+/-23 and G2 - 338+/-39 (GCxG1 p<0.01; GCxG2 p<0.001; G1xG2 p<0.01). State 4 mitochondrial respiration rate and respiratory control ratio (RCR) were similar in all groups (p>0.05). State 3 respirations (mM/min/mg) in GC, G1 and G2 was respectively: 99+/-23, 132+/-22 and 82+/-44 (p<0.02; the only statistical difference noted was between groups G1xG2 - p<0.05).


CONCLUSIONS
Following unilateral nephrectomy CRG is associated with an increase in state 3 of mitochondrial respiration. Renal ischemia/reperfusion injury enhances the CRG provoked by unilateral nephrectomy but such enhancement seems independent on mitochondrial respiration.
Tucci
Silvio
S
Division of Urology, Department of Surgery and Anatomy, Ribeirão Preto Faculty of Medicine, University of São Paulo, SP, Brazil. stucci@convex.com.br
Molina
Carlos Augusto Fernandes
CA
Cologna
Adauto José
AJ
Suaid
Haylton Jorge
HJ
Tirapelli
Luis Fernando
LF
Celini
Fábia Martins
FM
Martins
Antonio Carlos Pereira
AC
D000222:Adaptation, Physiological / Q000502:physiology; D000818:Animals; D004195:Disease Models, Animal; D007668:Kidney / Q000254:growth & development* / Q000503:physiopathology / Q000601:surgery; D008297:Male; D008928:Mitochondria / Q000502:physiology*; D009392:Nephrectomy; D009929:Organ Size; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000473:pathology* / Q000503:physiopathology; D013997:Time Factors; D052096:Warm Ischemia