Figure 6.

LPA induces COX-2 expression and PGE2 release through LPA₂. Tracheal epithelial cells from wild type and LPA₂^+/- mice were isolated as described in Materials and Methods and were cultured in 6-well plates. A) Total RNA was isolated and LPA receptors mRNA levels were measured by Real-time RT-PCR. B) Cells were challenged with 18:1LPA (1 μM) for 3 h, and COX-2 mRNA levels were measured by Real-time RT-PCR. (C). Cells were challenged with 18:1LPA (1 μM) for 3 h, and medium were collected. PGE2 levels in medium were measured by ELISA kit.