Table 1

Inhibitory effect of cPLA2 inhibitor AACOCF3 on PX-induced release of AA, PGE2, and dopamine (DA) in the presence of extracellular calcium

Compound[3H]AA ReleasePGE2 Release[3H]DA Release
cpm/2 × 106 cells pg/ml cpm/2 × 106 cells
PX1862  ± 1622600  ± 2502470  ± 200
PX +AACOCF3 758  ± 451-160 780  ± 1001-150 1141  ± 1101-160

PC-12 cells (2 × 106/well), labeled to steady state with [3H]AA, [3H]DA, or left unlabeled, were preincubated for 45 min with 25 μM AACOCF3 or left untreated. Thereafter, cultures were treated for 20 min with 5 μM PX or left untreated (control) in calcium-containing medium (1.8 mM). Samples of the culture medium were removed to measure radioactivity or for RIA, as described under Experimental Procedures. The values are the mean ± S.E.M. of three independent experiments (n= 3 in each experiment).

  • 1-150p < 0.05,

  • 1-160p < 0.01 compared with PX alone (the basal release was subtracted from all the values). The control, basal release of AA, PGE2, and dopamine was 700 ± 75 cpm/2 × 106 cells, 10 pg/ml, and 650 ± 40 cpm/2 × 106 cells, respectively.