Figure 2.

Influence of prostaglandins on nitrite production in the murine microglial cell line BV-2 (A and B), rat microglial cells (C), and rat astrocytes (D). Cells pretreated with the indicated concentrations of prostaglandins were stimulated with 0.4 ng/ml of LPS (microglia), 80 ng/ml of LPS (BV-2 and astrocytes), or 100 ng/ml of IL-1β (astrocytes). Control cultures were treated with diluent alone (C) or prostaglandins alone. Conditioned medium was collected at 12 h (microglia), 24 h (BV-2), or 48 h (astrocytes), and nitrite level was determined. Results are the mean ± SEM of n = 3 (BV-2) and n = 4 (microglia) independent experiments. For astrocytes, results of one of three representative experiments are shown. For BV-2 experiments, inhibition is expressed as percentage of control values, where the control is the nitrite level in cells stimulated with LPS alone.