Decreased Sodium Influx in Leaky Red Cell Membranes of the Patient with Familial Lecithin: Cholesterol Acyltransferase Deficiency

Abstract

Red cell membrane metabolism in familial LCAT deficiency was investigated. The family presented here was the third case in Japan. In addition to the marked abnormalities in lipid composition of red cell membranes, osmotic fragility of the red cells was decreased. Red cell surval (⁵¹Cr T 1/2) was 15 days. Sodium influx was markedly decreased, although sodium efflux, both ouabain-sensitive and-insensitive, was normal. The activity of acetylcholinesterase was decreased, while the activity of glyceraldehyde-3-phosphate dehydro-genase was normal. No abnormalities in red cell membrane proteins were observed.
These results suggest that the alterations of membrane permeability as well as increased membrane rigidity by accumulation of cholesterol and phosphatidyl choline might be related to the early demise of the red cells in this disoder.