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Updated: May 16, 2026
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A Modified Two Kidney One Clip Mouse Model of Renin Regulation in Renal Artery Stenosis
Published on: October 26, 2020
Structural analysis suggests that renin is released by compound exocytosis
Dominik Steppan1, Anita Zügner, Reinhard Rachel
1Physiologisches Institut der Universität Regensburg, Regensburg, Germany.
Kidney International
|December 14, 2012
Summary
This study reveals how renin is stored and released from kidney cells. Renin release involves vesicle fusion and emptying, similar to compound exocytosis, regardless of storage vesicle size.
Area of Science:
- Nephrology
- Cell Biology
- Endocrinology
Background:
- The precise mechanism of renin release from renal juxtaglomerular cells remains incompletely understood.
- Renin is a key enzyme in the renin-angiotensin-aldosterone system, regulating blood pressure and fluid balance.
Purpose of the Study:
- To investigate the intracellular organization of renin-storage vesicles.
- To analyze changes in these vesicles during stimulated renin release.
- To elucidate the exocytosis mechanism of renin release.
Main Methods:
- Utilized isolated perfused mouse kidneys for experiments.
- Employed 3-dimensional electron microscopy for detailed cellular analysis.
- Examined renin-producing cells in both wild-type and SCID-beige mice.
Main Results:
- Renin is stored in a network of granules and cavern-like structures, dependent on glycosylated prorenin synthesis.
- Acute renin release stimulation increased exocytosis, vesicle fusion into larger caverns, and subsequent emptying.
- Renin release rates were comparable between wild-type mice and SCID-beige mice with large storage vesicles.
Conclusions:
- Renin release appears to occur via a mechanism akin to compound exocytosis.
- The size and number of renin-storage vesicles do not significantly alter the release rate.
- Findings provide novel insights into the cellular regulation of renin secretion.
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