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Updated: Aug 12, 2026
10:14
An Efficient Sieving Method to Isolate Intact Glomeruli from Adult Rat Kidney
Published on: November 1, 2018
Polarity, integrin, and extracellular matrix dynamics in the postischemic rat kidney
A Zuk1, J V Bonventre, D Brown
1Renal Unit, Massachusetts General Hospital, Charlestown, MA 02129, USA.
The American Journal of Physiology
|September 9, 1998
Summary
Beta1-integrins change location during acute renal failure (ARF) from ischemic injury. These changes in beta1-integrins and fibronectin may contribute to ARF's development and repair processes.
Area of Science:
- Nephrology
- Cell Biology
- Pathophysiology
Background:
- Acute renal failure (ARF) affects 5% of hospitalized patients with high mortality.
- Little improvement in ARF survival rates over 40 years.
- Pathogenesis of ARF may involve altered cell-cell and cell-extracellular matrix interactions mediated by beta1-integrins.
Purpose of the Study:
- To examine integrin and extracellular matrix dynamics during epithelial injury and repair in a rat model of unilateral ischemia.
- To investigate the role of beta1-integrins in ARF pathophysiology.
Main Methods:
- In vivo rat model of unilateral ischemia.
- Analysis of beta1-integrin and fibronectin distribution in renal tubular epithelial cells post-ischemia.
- Assessment of cell polarity and exfoliation.
Main Results:
- Beta1-integrins redistribute from basal to apical surfaces during ischemic injury and repair.
- Newly appeared beta1-integrins on lateral borders in S3 segment epithelial cells post-reperfusion.
- Fibronectin found in tubular spaces of the distal nephron and S3 segments.
- Beta1-integrins not detected on exfoliated cells.
Conclusions:
- Beta1-integrin distribution changes dramatically during ischemic injury and epithelial repair in ARF.
- These alterations may contribute to initial cell exfoliation and later epithelial regeneration.
- Appearance of fibronectin in tubular lumens plays a significant role in ARF pathophysiology.
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