PRENATAL EXPOSURE TO ETHANOL INDUCES CHANGES IN THE NERVE GROWTH-FACTOR AND ITS RECEPTOR IN PROLIFERATING ASTROCYTES IN PRIMARY CULTURE

We have analyzed the effect of prenatal exposure to alcohol on the binding, internalization and secretion of NGF as well as on the content of the NGF receptor (NGFr) in cortical rat astrocytes in primary culture. Secretion of NGF was approximately 1.8-fold greater in 6-day control astrocytes than in 13-day cells. Intracellular content of NGF was very low. Astrocytes in 6-day cultures from control fetuses expressed a relatively large number of NGFr on the cell surface with a steady-state constant in the low nanomolar range. NGF was internalized by astrocytes at a slow rate. Prenatal exposure to ethanol induces a moderate increase in the number of NGFr on the cell surface as well. as an increase in the intracellular pool of both NGF and NGFr which is accompanied by an important reduction in the secretion of this factor. We speculate that this decrease in NGF secretion could alter the neuronal migration pattern during development, resulting in the presence of ectopic neurons in the cortex.