PGE₂ release in immortalized urothelial cells isolated from normal subjects (upper panel), primary human urothelial cells (HUC, middle panel) and IC/PBS patients (lower panel) after 20 ng/ml tryptase stimulation.

<p>PGE₂ release was measured in cells grown to confluence (Day 0, filled circles) or in cells stratified by the addition of FBS and calcium for 3 days (Day 3, open circles). Data shown are means ± SEM for triplicate experiments using cells isolated from 4 normal and 4 IC/PBS patients. **p<0.01,when compared to unstimulated controls.