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Updated: Jul 16, 2026
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A Standardized Method for the Analysis of Liver Sinusoidal Endothelial Cells and Their Fenestrations by Scanning Electron Microscopy
Published on: April 30, 2015
[Fluidity of hepatic microsomal membrane and its relation with aging]
A Pavese1, G Ouviña, A M Carbone
1Cátedra de Fisiopatología, Facultad de Farmacia y Bioquímica, U.B.A., Capital Federal, Argentina.
Acta Gastroenterologica Latinoamericana
|January 1, 1992
Summary
Aging significantly alters rat liver microsomal membranes, increasing phospholipid content and fluidity. These changes in phosphatidylcholine and other phospholipids may adapt enzyme activity for drug metabolism.
Area of Science:
- Biochemistry
- Cell Biology
- Gerontology
Context:
- Hepatic microsomal membranes are crucial for drug and carcinogen metabolism.
- Aging is known to induce significant physiological changes.
- Understanding age-related alterations in membrane composition is vital for predicting metabolic function.
Purpose:
- To investigate the impact of aging on the phospholipid composition of hepatic microsomal membranes in Wistar rats.
- To analyze age-dependent changes in specific phospholipid classes and their implications for membrane properties.
Summary:
- Aging (6 months vs. 2 months) in Wistar rats led to a 73% increase in total microsomal phospholipid content.
- Significant increases were observed in phosphatidylcholine (62%), phosphatidylserine (124%), phosphatidylinositol (31%), and sphingomyelin (10%).
- The phosphatidylcholine/ethanolamine plasmalogen index increased by 47%, indicating enhanced membrane fluidity in aged rats, with the appearance of phosphatidylethanolamine and phosphatidylglycerol.
Impact:
- Increased hepatic microsomal membrane fluidity during aging may represent an adaptive response.
- These compositional changes could influence the activity of enzymes involved in drug and carcinogen metabolism.
- Findings provide insights into age-related hepatic functional modifications and their biochemical underpinnings.
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