Differential protein expression in pancreatic islets after treatment with an imidazoline compound

T Jägerbrink1, H Lexander, C Palmberg

  • 1Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.

The effects of an imidazoline compound (BL11282) on protein expression in rat pancreatic islets were investigated with a proteomic approach. The compound increases insulin release selectively at high glucose concentrations and is therefore of interest in type 2 diabetes. Whole cell extracts from isolated drug-treated and native pancreatic rat islets were compared after separation by 2-D gel electrophoresis. Differentially expressed proteins were identified by mass spectrometry; 15 proteins were selectively up-regulated and 7 selectively down-regulated in drug-treated islets. Of special interest among the differentially expressed proteins are those involved in protein folding (Hsp60, protein disulfide isomerase, calreticulin), Ca(2+) binding (calgizzarin, calcyclin and annexin I) and metabolism or signalling (pyruvate kinase, alpha enolase and protein kinase C inhibitor 1).

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