Related Experiment Video
Updated: Sep 1, 2026
Analysis of Fluorescent-Stained Lipid Droplets with 3D Reconstruction for Hepatic Steatosis Assessment
Published on: June 2, 2023
A biochemical and morphological study of rat liver microsomes
Abstract:
Microsomes isolated by differential centrifugation from a rat liver homogenate in 0.88 M sucrose solution have been studied from the biochemical and morphological point of view. 1. Under these experimental conditions, the "total microsome" fraction was obtained by centrifuging the cytoplasmic extract free of nuclei and mitochondria, for 3 hours at 145,000 g. Morphologically, the total microsomes consist mainly of "rough-surfaced membranes" and "smooth" ones. 2. The total microsomes have been divided into 2 subfractions so that the 1st microsomal fraction contains the "rough" vesicles (2 hours centrifugation at 40,000 g) while the 2nd microsomal fraction consists essentially of smooth vesicles, free particles, and ferritin (centrifugation of the supernatant at 145,000 g for 3 hours). 3. By the action of 0.4 per cent sodium deoxycholate in 0.88 M sucrose, it was possible to obtain a pellet for each of the 2 fractions which consisted of dense particles, rich in RNA, poor in lipids, and which represented about 50 to 60 percent of the RNA and 10 to 15 per cent of the proteins. The results have been discussed taking into consideration the hypothesis of the presence of RNA in the membranes of microsomal vesicles.
Insights
Rat liver microsomes were isolated and separated into rough and smooth fractions. These fractions, when treated with sodium deoxycholate, yielded RNA-rich particles, suggesting RNA presence within microsomal membranes.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Biology
Background:
- Microsomes are crucial cellular components involved in various metabolic processes.
- Understanding microsomal composition is key to deciphering cellular functions.
Purpose of the Study:
- To biochemically and morphologically characterize rat liver microsomes.
- To investigate the subfractionation of microsomes and their composition.
Main Methods:
- Rat liver homogenate was subjected to differential centrifugation in 0.88 M sucrose.
- Microsomes were isolated and separated into rough and smooth subfractions.
- Sodium deoxycholate treatment was used to analyze the composition of microsomal fractions.
Main Results:
- The total microsome fraction comprised rough and smooth membranes.
- Two subfractions were obtained: rough vesicles and smooth vesicles with free particles and ferritin.
- Sodium deoxycholate treatment yielded RNA-rich, lipid-poor particles from both fractions.
Conclusions:
- The study provides biochemical and morphological insights into rat liver microsomes.
- Results support the hypothesis of RNA presence within microsomal vesicle membranes.
- Further research can explore the functional implications of RNA in microsomes.
