Exposure of Pulmonary Artery Endothelial Cells to Nitrogen Dioxide Activates Phospholipase A1

✍ Scribed by Bhat, G. B. ;Patel, J. M. ;Block, E. R.

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 294 KB
• Volume: 5
• Category: Article
• ISSN: 0887-2082
• DOI: 10.1002/jbt.2570050111

✦ Synopsis

Abstract

Phospholipase A~1~, A~2~, and C and diacylglycerol lipase activities were measured in cell sonicates after exposing confluent monolayers of porcine pulmonary artery endothelial cells to 5 ppm NO~2~, a toxic constituent of environmental pollution, for 24 and 48 hr. There was a significant increase (2.25‐fold) in phospholipase A~1~ activity in 24 and 48 hr NO~2~‐exposed cells, whereas activities of phospholipases A~2~ and C and diacylglycerol lipase were comparable to control cells at both time points. When endothelial cells were prelabeled with [^3^H]‐arachidonic acid and then exposed to NO~2~ for 48 hr, increased counts were recovered from cell lysophospholipids with concomitant decreased recovery of counts from cell phosphatidylcholine and phosphatidylethanolamine. These results demonstrate that NO~2~ exposure results in specific activation of phospholipase A~1~.