Insulinotropin PACAP potentiates insulin-stimulated glucose uptake in 3T3 L1 cells

Peptides. 1999;20(8):943-8. doi: 10.1016/s0196-9781(99)00085-6.


Pituitary adenylate cyclase-activating polypeptide (PACAP) is localized in pancreatic nerve fibers and islets and potently augments glucose-induced insulin secretion. The present study explored a possible extra-pancreatic action of PACAP. The specific PACAP receptor (PAC1 receptor) was expressed in the rat fat tissue and 3T3-LI adipocytes. PACAP-38 (10 nM) significantly enhanced insulin-induced 2-deoxyglucose uptake by 3T3-L1 adipocytes. Insulin-stimulated phosphatidylinositol 3-kinase activity was further increased by PACAP-38, whereas the tyrosine-phosphorylation of insulin receptor beta-subunit and insulin receptor substrate-1 was unaltered by PACAP-38. These results reveal that PACAP-38 enhances insulin-induced glucose uptake, an effect probably mediated by insulin-stimulated phosphatidyl-inositol 3-kinase, and that PACAP potentiates not only insulin secretion, but also insulin action in adipocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3 Cells
  • Amino Acid Sequence
  • Animals
  • Enzyme Activation
  • Glucose / metabolism*
  • Immunohistochemistry
  • Insulin / metabolism*
  • Insulin / pharmacology
  • Insulin Receptor Substrate Proteins
  • Mice
  • Molecular Sequence Data
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphoproteins / metabolism
  • Rats


  • Insulin
  • Insulin Receptor Substrate Proteins
  • Irs1 protein, mouse
  • Irs1 protein, rat
  • Phosphoproteins
  • Phosphatidylinositol 3-Kinases
  • Glucose