Figure 4
No additive or synergistic effects of combinations of MK-801 and ketamine on macrophage TNF secretion, in response to antibiotic-treated CA-MRSA strain MW2, were seen. Bacteria were added at a final concentration of 105 to107 CFU/mL (retrospective confirmation) in the presence of either vancomycin at 20 μg/mL (upper panel) or daptomycin at 20 μg/mL (lower panel). One hour prior to stimulation, either ketamine at 100 μM, MK-801 at 150 μΜ, or both were added to the indicated wells. Cells were then incubated for 18 hours; supernatants were collected and analyzed for TNF content by ELISA. Lane 1 (control) represents the mean TNF production by macrophages not stimulated with bacteria. The mean includes wells exposed to ketamine, MK-801, both ketamine and MK-801, and neither. In the absence of bacteria, TNF secretion was minimal and was not affected by ketamine and/or MK-801. Lanes 2 -5 depict mean TNF secretion by macrophages exposed to vancomycin-treated MW2 alone (lane 2), MW2 + ketamine (lane 3), MW2 + MK-801 (lane 4), or MW2 + ketamine + MK-801 (lane 5). The "*" on bars 3, 4, 5 indicates that they are statistically different (p < 0.05) from bars 1 and 2. The "**" on bar 2 indicates significantly higher TNF production (p < 0.05).