PGD2 production and up-regulation of COX-2 expression by LAD2
cells in response to cys-LTs and the involvement of PPARγ in mediating
these effects. A, dose response of cys-LT-mediated
PGD2 generation in LAD2 cells stimulated with the indicated
concentrations of cys-LTs for 6 h. B, time course of PGD2
generation by LAD2 cells stimulated for the indicated intervals with
LTD4 (500 nm) or LTE4 (500 nm).
C, real-time PCR showing relative levels of COX-2 transcript
expression by LAD2 cells stimulated with 100 nm LTD4 or
LTE4 for 2 h. Data in A–D are the mean ± S.E.
from three experiments each. D, time course of COX-2 protein
induction in cells stimulated with LTD4 (100 nm) and
LTE4 (100 nm) for the indicated periods of time. Data
are from a single experiment representative of the three performed.
E, effect of GW9662 (10 μm, 1 h) on COX-2 protein
up-regulation in response to LTD4 and LTE4 (100
nm for 4 h each,). Data are from a single experiment representative
of three performed. F, effect of pretreatment with GW9662 (10
μm, 1h), PD98059 (50 μm, 30 min), and NS398 (10
μm, 30 min) on LTE4-induced generation of
PGD2 (measured 6 h after stimulation) by LAD2 cells. Data depicted
are the mean ± S.D. of three independent experiments. PGD2
was quantitated with a PGD2-MOX assay.