Silica Induced Phospholipase D (PLD) Activation in Rat2 Fibroblasts = Silica Induced Phospholipase D (PLD) Activation in Rat2 Fibroblasts

다국어 초록 (Multilingual Abstract)

To define the effect of silica on the stimulator of signaling pathway, we studied the phospholipase D (PLD) activity in the Rat2 fibroblasts. Silica stimulated the accumulation of labeled [³H] phosphatidylethanol([³H] PEt) in a time- and concentration-dependent manner. This Silicainduced PLD activity was partially attenuated by the pretreatment with U73122 (phospholipase C inhibitor), genistein (protein tyrosine kinase inhibitor), PD 98056 (MEK inhibitor) and mepacrine (phospholipase A₂ inhibitor). But, sphingosine (protein kinase C inhibitor) and DPI (NADPH reductase inhibitor) had not effect the PLD activity. Silica also increased the PLA₂ activity about four fold, which imply that the PLD activity is more influenced by the mobilization of PLA₂ than other signaling mediators. The PLD activity also partially inhibited calcium chelator EGTA or/and BAPTA/AM compared to silica. Finally, we concluded that a silica-stimulated phospholipase D activity is present in the Rat2 fibroblasts and is modulated by combination of various signaling mediators.

목차 (Table of Contents)

• ABSTRACT
  
• INTRODUCTION
  
• MATERIALS AND METHODS
  
• RESULT
  
• DISCUSSION
  
• ACKNOWLEDGEMENTS
  
• REFERENCES

참고문헌 (Reference)

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