FEBS Letters · 1990 · 46 citations · 18 references
Life SciencesCell BiologyPharmacologyCell SignalingMolecular PharmacologySignal TransductionAstrocyte BiologyCyclic Nucleotide SignalingPhosphoinositide SignalingGtp Hydrolysis RegulationInositol Phosphate SignalingInositol Triphosphate SignalingInositol Trisphosphate SignalingPhosphatidylinositol 3, 4, 5-Trisphosphate SignalingPhosphatidylinositol 4, 5-BisphosphatePhosphodiesterase InhibitionPhospholipase C Pathway
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.
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