Fig. 3

Time course of plasma cytokine levels at 2- and 4-h post-ketamine infusion (0 or 10 mg/kg) in male and female rats. Data are presented as changes from the saline control group. The saline infusion did not change any of the cytokine levels at 2- and 4-h post-infusion in male and female rats. However, ketamine-induced reduction of cytokine levels at 2-h post-infusion returned to the control levels at 4-h post-infusion, except for IL-6 levels in male rats. This indicates that a 10 mg/kg ketamine infusion produces a delayed reduction of IL-6 levels in male rats only (3C). The sample sizes for cytokines (2 h and 4 h): IL-4 (n = 23, 21 for saline males and n = 11, 15 for saline females; n = 18, 19 for ketamine males and n = 11, 10 for ketamine females), IL-5 (n = 24, 12 for saline males and n = 14, 14 for saline females; n = 18, 15 for ketamine males and n = 9, 13 for ketamine females), IL-6 (n = 25, 13 for saline males and n = 19, 17 for saline females; n = 19, 18 for ketamine males and n = 15, 16 for ketamine females), IL-10 (n = 25, 21 for saline males and n = 18, 20 for saline females; n = 18, 19 for ketamine males and n = 16, 16 for ketamine females), KC/GRO (n = 24, 20 for saline males and n = 25, 21 for saline females; n = 18, 18 for ketamine males and n = 24, 21 for ketamine females), TNF-α (n = 25, 21 for saline males and n = 25, 21 for saline females; n = 19, 19 for ketamine males and n = 25, 22 for ketamine females)