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A Modified Two Kidney One Clip Mouse Model of Renin Regulation in Renal Artery Stenosis
Published on: October 26, 2020
ON THE NATURE OF THE PRESSOR ACTION OF RENIN
1Lilly Laboratory for Clinical Research, Indianapolis City Hospital, Indianapolis.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Repeated renin injections cause tachyphylaxis in animals, a response linked to a loss of renin-activator. Restoring this activator can reverse the effect, highlighting its role in renin
Area of Science:
- Cardiovascular Physiology
- Renal Physiology
Background:
- Renin plays a crucial role in blood pressure regulation.
- Tachyphylaxis, a rapid decrease in response to a drug, has been observed with repeated renin administration.
Purpose of the Study:
- To investigate the mechanisms underlying renin-induced tachyphylaxis.
- To identify factors influencing the pressor response to renin.
Main Methods:
- Repeated intravenous injections of renin in various animal models (dogs, cats).
- Surgical manipulations including hepatectomy, suprarenalectomy, nephrectomy, and evisceration.
- Isolated rabbit ear perfusion studies with renin and renin-activator.
- Analysis of blood samples for renin-activator content.
Main Results:
- Tachyphylaxis to renin occurs consistently across different experimental conditions.
- The pressor response to renin is largely independent of arterial pressure and adrenal glands but is reduced by evisceration and ergotamine.
- Renin-activator is essential for renin's vasoconstrictive activity in isolated systems.
- Blood from tachyphylactic animals lacks renin-activator, and its addition restores renin's efficacy.
Conclusions:
- Renin-induced tachyphylaxis is mediated by the depletion of a blood factor, termed renin-activator.
- The presence and activity of renin-activator are critical for maintaining the pressor response to renin.
- Understanding renin-activator dynamics is key to managing renin-based therapies and understanding cardiovascular regulation.
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