AJP - Renal Physiology, Vol 251, Issue 1 87-F93, Copyright © 1986 by American Physiological Society
Body temperature: an important determinant of severity of ischemic renal injury
R. A. Zager and R. Altschuld
To assess the effects of body temperature on renal susceptibility to
ischemic injury, rats were rendered acutely hypothermic (90-93 degrees F),
normothermic (98-99 degrees F), or hyperthermic (101-103 degrees F) with a
heat-controlled surgical board and then were subjected to 25 min of
bilateral renal artery occlusion (RAO). Renal high-energy phosphates, their
degradation products, and nonprotein sulfhydryl (NPSH) content were
assessed at selected times during the peri-ischemic period. The severity of
acute renal failure (ARF) was determined for 48 h following RAO by blood
urea nitrogen (BUN) and plasma creatinine determinations and by renal
histology. Ischemic ATP, ADP, AMP, GTP, GDP, UTP, and NAD levels and
postischemic NPSH levels (15 min reflow) inversely correlated with
temperature (P less than 0.001). BUN, creatinine concentrations (at 24 and
48 h), and histological injury (at 48 h) directly correlated with
temperature (P less than 0.01). Hyperthermia in the absence of RAO had no
demonstrable adverse renal effects. We conclude that hyperthermia
potentiates ischemic renal injury, whereas hypothermia confers protection.
These effects are associated with, and may be influenced by,
temperature-induced changes in renal high-energy phosphate availability and
oxidant stress during the ischemic/postischemic period.
