Modulation of inducible nitric oxide synthase in RINm5F cells

Cell Signal. 1994 Jan;6(1):17-24. doi: 10.1016/0898-6568(94)90057-4.


The rat insulinoma beta-cell line RINm5F, which shares some homology with pancreatic islets, was used to study nitric oxide synthase induction. Nitric oxide is involved during beta-cell destruction and possibly in propagation of insulin-dependent diabetes mellitus. The cytokine interleukin-1 (IL-1) turned out to be the ultimate inducer, whereas tumour necrosis factor-alpha (TNF) and unexpectedly the phorbol ester TPA (12-O-tetradecanoylphorbol-13-acetate; 10 nM) synergistically promoted nitrite accumulation. Besides employing TPA directly, the synergistic effect of TNF could be traced back to protein kinase C activation since protein kinase C inhibitors (IC50 value for staurosporine: 4 nM) potently suppressed nitrite production in the case of IL-1/TNF administration. Further experiments using anti-TNF antibodies aimed to an autocrine loop following IL-1 addition to RINm5F cells, possibly involved in nitrite generation. Moreover, the nitric oxide synthase inductive IL-1 signal was antagonized by lipophilic cAMP analogues. Our results for nitrite accumulation in RINm5F cells point to activating protein kinase C and inhibitory protein kinase A signalling pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Oxidoreductases / biosynthesis*
  • Animals
  • Cyclic AMP / analogs & derivatives
  • Cyclic AMP / pharmacology
  • Drug Synergism
  • Enzyme Induction
  • Interleukin-1 / antagonists & inhibitors
  • Interleukin-1 / pharmacology
  • Islets of Langerhans / drug effects
  • Islets of Langerhans / enzymology*
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase
  • Nitrites / metabolism
  • Protein Kinase C / metabolism
  • Rats
  • Signal Transduction / drug effects
  • Tetradecanoylphorbol Acetate / pharmacology
  • Tumor Cells, Cultured
  • Tumor Necrosis Factor-alpha / pharmacology


  • Interleukin-1
  • Nitrites
  • Tumor Necrosis Factor-alpha
  • Nitric Oxide
  • Cyclic AMP
  • Nitric Oxide Synthase
  • Amino Acid Oxidoreductases
  • Protein Kinase C
  • Tetradecanoylphorbol Acetate