Mastoparan inhibits phosphoinositide hydrolysis via pertussis toxin-insensitive [corrected] G-protein in human astrocytoma cells

FEBS Lett. 1990 Jan 15;260(1):91-4. doi: 10.1016/0014-5793(90)80074-s.

Abstract

Mastoparan inhibited [3H]inositol phosphate accumulation induced by carbachol as well as cyclic AMP accumulation induced by isoproterenol in 1321N1 human astrocytoma cells. Mastoparan inhibited GTP gamma S-induced, but not Ca2(+)-induced, [3H]inositol phosphate accumulation in membrane preparations with an IC50 of approximately 10 microM. The inhibitory effect of mastoparan on carbachol-induced [3H]inositol phosphate accumulation was resistant to pertussis toxin (IAP) treatment in intact cells. These results suggest that mastoparan inhibits phospholipase C in human astrocytoma cells via a GTP binding protein, which is not a substrate for IAP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Astrocytoma / enzymology
  • Astrocytoma / metabolism*
  • Bee Venoms / pharmacology*
  • Calcium / pharmacology
  • Cyclic AMP / metabolism
  • Dose-Response Relationship, Drug
  • GTP-Binding Proteins / pharmacology*
  • Guanosine Triphosphate / antagonists & inhibitors
  • Guanosine Triphosphate / pharmacology
  • Humans
  • Hydrolysis
  • Inositol Phosphates / metabolism
  • Intercellular Signaling Peptides and Proteins
  • Peptides
  • Pertussis Toxin
  • Phosphatidylinositols / metabolism*
  • Tumor Cells, Cultured / drug effects
  • Type C Phospholipases / antagonists & inhibitors
  • Virulence Factors, Bordetella / pharmacology
  • Wasp Venoms / antagonists & inhibitors
  • Wasp Venoms / pharmacology*

Substances

  • Bee Venoms
  • Inositol Phosphates
  • Intercellular Signaling Peptides and Proteins
  • Peptides
  • Phosphatidylinositols
  • Virulence Factors, Bordetella
  • Wasp Venoms
  • mastoparan
  • Guanosine Triphosphate
  • Cyclic AMP
  • Pertussis Toxin
  • Type C Phospholipases
  • GTP-Binding Proteins
  • Calcium