AJP - Cell Physiology, Vol 249, Issue 5 476-C483, Copyright © 1985 by American Physiological Society
Effect of renal ischemia on cortical microsomal calcium accumulation
A. Schieppati, P. D. Wilson, T. J. Burke and R. W. Schrier
Mitochondrial respiration, Ca2+ content, and Ca2+ kinetics have been found
to be profoundly altered in ischemic acute renal failure (ARF). The effect
of clamping the bilateral renal artery for 50 and 90 min on microsomal Ca2+
uptake was therefore examined in the rat. The 50-min clamping produced a
reversible model of nonoliguric ARF, and the 90-min clamping produced a
model of nonreversible oliguric ARF. In the 50-min nonoliguric model,
ATP-dependent Ca2+ uptake by microsomes from renal cortex (nmol X mg
protein-1 X 30 min-1) was significantly impaired immediately before release
of the clamp and before return of renal blood flow (reflow) (191 +/- 11 vs.
83 +/- 11, P less than 0.005). However, in this nonoliguric model of
ischemic ARF, microsomal uptake returned completely to normal after 1 h of
reflow (sham 189 +/- 11 vs. 167 +/- 14 at 1 h, NS) and persisted at this
normal level at 24 h (sham 166 +/- 14 vs. 150 +/- 13 at 24 h, NS). In the
oliguric model of ARF the microsomal Ca2+ uptake also was impaired
immediately after the clamp release (sham 191 +/- 11 vs. 93 +/- 11, P less
than 0.001) as well as after 1 h of reflow (sham 189 +/- 11 vs. 129 +/- 12,
P less than 0.005) but not at 24 h (sham 166 +/- 14 vs. 173 +/- 13, NS).
The results indicate that impaired microsomal Ca2+ uptake occurs early in
both oliguric and nonoliguric ARF and persists after 1 h of reflow in the
oliguric model.(ABSTRACT TRUNCATED AT 250 WORDS)
