Functional Properties of the Subtype of Insulin Receptor Found on Neurons

摘要: In this report, we have examined the structure, regulation, and function of insulin receptors in cultured neurons from fetal chicken brain. The apparent molecular weight alpha-subunit neuronal receptors, analyzed by photoaffinity labeling sodium dodecyl sulfate gel electrophoresis under reducing conditions, was 115,000. number cultures increased day 2 to 4 during a period extensive process formation. After 5 days culture, there were approximately 40,000 high-affinity per neuron. When labeled at 16 degrees C then warmed 37 for 30 min, 40% cell-surface recovered intracellular, trypsin-insensitive pool. Chronic exposure (100 ng/ml) resulted time-dependent loss with maximal decrease 50% after 24 h. Insulin had no effect on glucose transport, oxidation, or glycogen synthase activity neurons. On other hand, supported growth differentiation fraction isolated chick forebrain. We conclude that (1) brain express same subtype receptor previously identified adult rat human brain, (2) undergoes internalization down-regulation response insulin, (3) do not acutely regulate metabolism but mediate