Premium
Protective Effect Of α‐LIPOIC Acid Against Ischaemic Acute Renal Failure In Rats
Author(s) -
Takaoka Masanori,
Ohkita Mamoru,
Kobayashi Yutaka,
Yuba Mikihiro,
Matsumura Yasuo
Publication year - 2002
Publication title -
clinical and experimental pharmacology and physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 103
eISSN - 1440-1681
pISSN - 0305-1870
DOI - 10.1046/j.1440-1681.2002.03624.x
Subject(s) - renal function , creatinine , blood urea nitrogen , medicine , urology , nephrectomy , fractional excretion of sodium , renal ischemia , kidney , endocrinology , lipoic acid , renal artery , ischemia , chemistry , reperfusion injury , antioxidant , biochemistry
SUMMARY 1. In the present study, we investigated whether treatment with α ‐lipoic acid (LA), a powerful and universal anti‐oxidant, has renal protective effects in rats with ischaemic acute renal failure (ARF). 2. Ischaemic ARF was induced by occlusion of the left renal artery and vein for 45 min followed by reperfusion, 2 weeks after contralateral nephrectomy. Blood urea nitrogen (BUN), plasma concentrations of creatinine (P cr ) and urinary osmolality (U osm ) were measured for the assessment of renal dysfunction. Creatinine clearance (C cr ) and fractional excretion of Na + (FE Na ) were used as indicators of glomerular and tubular function, respectively. 3. Renal function in ARF rats decreased markedly 24 h after reperfusion. Intraperitoneal injection of LA at a dose of 10 mg/kg before the occlusion tended to attenuate the deterioration of renal function. A higher dose of LA (100 mg/kg) significantly ( P < 0.01) attenuated the ischaemia/reperfusion‐induced increases in BUN (19.1 ± 0.7 vs 7.2 ± 0.7 mmol/L before and after treatment, respectively), P cr (290 ± 36 vs 78.1 ± 4.2 μ mol/L before and after treatment, respectively) and FE Na (1.39 ± 0.3 vs 0.33 ± 0.09% before and after treatment, respectively). Treatment with 100 mg/kg LA significantly ( P < 0.01) increased C cr (0.70 ± 0.13 vs 2.98 ± 0.27 mL/min per kg before and after treatment, respectively) and U osm (474 ± 39 vs 1096 ± 80 mOsmol/kg before and after treatment, respectively). 4. Histopathological examination of the kidney of ARF rats revealed severe lesions. Tubular necrosis ( P < 0.01), proteinaceous casts in tubuli ( P < 0.01) and medullary congestion ( P < 0.05) were significantly suppressed by the higher dose of LA. 5. A marked increase in endothelin (ET)‐1 content in the kidney after ischaemia/reperfusion was evident in ARF rats (0.43 ± 0.02 ng/g tissue) compared with findings in sham‐ operated rats (0.20 ± 0.01 ng/g tissue). Significant attenuation ( P < 0.01) of this increase occurred in ARF rats treated with the higher dose of LA (0.24 ± 0.03 ng/g tissue). 6. These results suggest that administration of LA to rats prior to development of ischaemic ARF prevents renal dysfunction and tissue injury, possibly through the suppression of overproduction of ET‐1 in the postischaemic kidney.