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Updated: Aug 9, 2026

Fluorescence-Based Measurements of Phosphatidylserine/Phosphatidylinositol 4-Phosphate Exchange Between Membranes
Published on: March 14, 2021
[Changes in the level of tightly-bound mitochondrial phospholipids induced by exogenous factors]
Abstract:
The effects of some parameters of the incubation medium (tonicity, H+ and Pi concentration) on the phospholipid content in rat mitochondrial extracts prepared by normal extraction and by extraction with strongly acidified solvent mixtures, were studied. It was found that after normal extraction with a chloroform-methanol mixture, 8% to 25% of mitochondrial phospholipids can be additionally extracted by acidified solvent mixtures. The concentration of weakly extractable lipids depends on the tonicity and ionic composition of the incubation medium. It was suggested that there exist in mitochondria two lipid pools, a loosely and a tightly-bound ones; the equilibrium between these pools is effectively regulated by medium tonicity and other external factors.
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