Endocrinology, Vol 108, 2014-2016, Copyright © 1981 by Endocrine Society

ARTICLES

Insulin induced alterations of acyl groups of the cerebroside fraction isolated from fat cell ghosts

DK Murray and DH Nelson

Rat epididymal fat cells were isolated and incubated with 25 microunits insulin/ml for 15 minutes. Insulin induced a significant shift in the saturated/unsaturated fatty acid ratio of the cerebroside fraction isolated from fat cell ghosts. This change was due to a decrease of saturated fatty acids and an increase of unsaturated fatty acids which were hydrolyzed from the isolated lipids. There were no significant changes in the amount of phospholipids isolated from the fat cell ghosts after this period of incubation with insulin or of fatty acids associated with them. Isolated adipocytes were also incubated with 8 x 10(-8) M dexamethasone for 2 1/2 hours. Insulin (25 microunits/ml) was then added, and the incubation continued for 15 minutes. Dexamethasone treated cells did not show a statistically significant insulin stimulated decrease in the saturated/unsaturated fatty acid ratio. These studies demonstrate an insulin induced change in membrane lipids which appeared to be partially blocked by previous exposure to dexamethasone.