Figure 1.
GTPγS stimulation of lactoferrin release from streptolysin O–permeabilized PMNs: inhibition by C2-ceramide. PMNs were first incubated with 50 μM lipid, then added to tubes containing (final concentrations) 75 U/mL streptolysin O, GTPγS as indicated, 1 mM ATP, and 3 μM Ca++. Samples were incubated for 10 minutes at 37°C. PMNs were removed by centrifugation, and supernatants were assayed for lactoferrin by ELISA. Data shown are the mean ± SEM of 4 experiments. *Significantly different from stimulated control; P < .001; dihydro-C2-ceramide not significantly different from control at P = .05.
