Evidence that an L-fucose-containing component in the beta-cell plasma membrane is involved in the regulation of glucose-induced insulin release.
The effect of the L-fucose-selective lectin Ulex Europeus I (UEA I), a blocker of the Na+, K+, Cl- co-transport system in the kidney, was tested on insulin secretion from isolated beta-cell-rich pancreatic islets. UEA I at doses from 50 to 100 micrograms ml-1 significantly reduced the glucose-induced (20 mmol l-1) insulin release whereas the basal (3 mmol l-1) release was unaffected. The inhibitory effect of 100 micrograms ml l-1 UEA I was completely abolished by 10 mmol l-1 L-fucose. The data suggest that an L-fucose-containing structure in the beta-cell plasma membrane participates in the regulation of glucose-induced insulin release. This structure may be similar to the L-fucose-containing glycoprotein in the kidney tubules that is believed to be the Na+, K+, Cl- cotransporter.
Sandström
P E
PE
Department of Histology and Cell Biology, University of Umeå, Sweden.
Sehlin
J
J
D000818:Animals; D002462:Cell Membrane / Q000032:analysis; D005643:Fucose / Q000008:administration & dosage / Q000032:analysis; D005947:Glucose / Q000008:administration & dosage*; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000032:analysis / Q000378:metabolism*; D037102:Lectins / Q000008:administration & dosage*; D051379:Mice; D008820:Mice, Obese; D037121:Plant Lectins
D007328:Insulin; D037102:Lectins; D037121:Plant Lectins; C036850:Ulex europaeus lectins; D005643:Fucose; D005947:Glucose