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Updated: May 30, 2026
12:03
Receptor Autoradiography Protocol for the Localized Visualization of Angiotensin II Receptors
Published on: June 7, 2016
Identification and characterization of a functional mitochondrial angiotensin system
Peter M Abadir1, D Brian Foster, Michael Crow
1Division of Geriatric Medicine and Gerontology, Biology of Healthy Aging Program, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
Summary
Scientists discovered a functional angiotensin system within mitochondria, impacting nitric oxide production and respiration. This finding reveals new therapeutic targets for aging and chronic diseases.
Area of Science:
- Biochemistry
- Cell Biology
- Physiology
Background:
- The renin-angiotensin system (RAS) regulates physiological functions via Ang II type 1 and type 2 receptors.
- Previous research suggested intracellular and nuclear pools of Ang II, but a mitochondrial RAS was undescribed.
Purpose of the Study:
- To investigate the presence and function of a RAS within human mitochondria.
- To explore the role of mitochondrial RAS in nitric oxide production, respiration, and age-related changes.
Main Methods:
- Immunohistochemistry to detect Ang II type 2 receptors and endogenous Ang in mitochondrial inner membranes.
- Assessment of mitochondrial nitric oxide production and respiration.
- Analysis of mitochondrial Ang receptor expression in aging and after losartan treatment.
Main Results:
- Functional Ang II type 2 receptors were identified on mitochondrial inner membranes, colocalized with Ang II.
- Mitochondrial RAS activation influenced nitric oxide production and modulated mitochondrial respiration.
- Aging led to increased mitochondrial Ang II type 1 receptor and decreased type 2 receptor expression, reversible with losartan.
Conclusions:
- A functional RAS exists within human mitochondria, influencing key cellular processes.
- Mitochondrial RAS plays a role in age-related mitochondrial dysfunction.
- Targeting mitochondrial RAS offers potential therapeutic strategies for aging and chronic diseases.
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