FIG. 5.
NO release, as evaluated by the measurement of nitrites (mean + SEM) in cell-free BAL fluid 15 min and 2 h after the 5th injection of L-NMMA. Infection was induced by intranasal inoculation of 3.5 × 107 CFU of S. pneumoniae/mouse at time zero, and L-NMMA was injected s.c. at doses of 3 mg/kg every 12 h, initiated just before the infection. Comparisons indicated by the asterisks (∗, P < 0.05, and ∗∗, P < 0.01) were made between infected animals and their respective controls (infected versus control and infected plus L-NMMA versus L-NMMA).