REgulation of insulin binding to isolated hepatocytes: correction for bound hormone fragments linearizes Scatchard plots

摘要: Abstract Fragments of 125I-labeled insulin (125I-insulin) are rapidly produced after the initial cell binding process. After association 125I-insulin with hepatocytes, hormone fragments remain bound to cells. At 23 degrees C, approximately 20% label at steady state was soluble in trichloroacetic acid. Correction saturation experiments for presence acid-soluble decreased number and increased affinity 125I-insulin-binding sites. Label extracted from pellets recovered characterized by gel filtration; 59%, 55%, 40%, 36% intact recovery incubation mixtures containing 0.18, 0.60, 4.6, 7.5 nM applied 125I-insulin, respectively. high concentrations, predominantly interacted lower degradation systems. When data were corrected assay undegraded only, curvilinear Scatchard plots linearized. The receptor is therefore not composed heterogeneous or negatively cooperative It necessary correct retained order define mechanisms through which cellular response may be regulated.