Transmembrane movement of cholesterol in human erythrocytes.

Transmembrane movement of cholesterol in human erythrocytes.

We studied the exchange of cholesterol between radioactively labeled plasma and human erythrocytes. Results from experiments in which [3H]cholesterol and [14C]-cholesterol were exchanged sequentially into the cells and back out into unlabeled plasma, showed that transmembrane movement of cholesterol occurred with a half-time that was either less than 50 min or greater than 10 days. To obtain fu...

Transmembrane movement of diether phospholipids in human erythrocytes and human fibroblasts.

We have synthesized spin-labeled (SL) and fluorescently labeled diacyl, 1-alkyl-2-acyl-, and di-alkyl glycerophospholipids. The sn-2 chain was a short chain with either a nitroxide group or a 7-nitro-2, 1,3-benzoxadiazol-4-yl (NBD). After incorporation in the exoplasmic leaflet of human erythrocytes, we found that SL-phosphatidylcholine (PC) redistributed very slowly across the plasma membrane,...

Transmembrane orientation of the glycoproteins in normal human erythrocytes.

Movement of cholesterol in vitro in rat blood and quantitation of the exchange of free cholesterol between plasma and erythrocytes.

After administration of [4-(14)C]cholesterol to rats, blood was obtained and incubated for 6 hr or less. Incubation resulted in a net loss of erythrocyte cholesterol and, simultaneously, in an increase of esterified cholesterol in plasma and alpha-lipoproteins. Erythrocyte labile cholesterol was shown to be the sole precursor of esterified cholesterol. However, the relation between loss and est...

Vibratory movement in the cytoplasm of erythrocytes.

In 1890 Browicz described an intracellular vibratory movement in human erythrocytes, which he believed to be a pathological condition, from four cases of anaemia. It was found in one case of pernicious anaemia, and was stated to disappear following a remission; it was also found in two cases of malignant disease. He ascribed it to abnormal reactions between pathological erythrocytes and their p...