title: Marked increase in insulin sensitivity of human fat cells 1 hour after glucose ingestion.
abstract: The effect of glucose ingestion on insulin action was investigated in isolated human fat cells. Subcutaneous adipose tissue was obtained from eight normal adult volunteers before and 1 h after oral intake of 100 g of glucose. Lipolysis (glycerol release) and specific insulin receptor binding were determined. Insulin binding increased significantly by 20-30% after glucose ingestion. This was due to an increase in insulin binding affinity, without any change in the receptor number. The concentration of insulin producing half-maximum inhibition (ED(50)) of basal lipolysis was 50 muU/ml before and 0.25 muU/ml after glucose ingestion (P < 0.01), which represented a 200-fold difference. As regards isoprenaline-induced lipolysis, the ED(50) for insulin inhibition was 30 muU/ml before and 2.5 muU/ml after oral glucose (P < 0.01), which was a 12-fold difference. The maximum insulin-induced inhibition of basal and isoprenaline-induced lipolysis were not altered after oral glucose. It is concluded that glucose ingestion is accompanied by a marked increase in insulin sensitivity of human fat cells and this may be an important modulating factor in the overall scheme of insulin action.
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D005260:Female; D005947:Glucose / Q000494:pharmacology*; D005990:Glycerol / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007328:Insulin / Q000097:blood / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D007328:Insulin; D005947:Glucose; D005990:Glycerol