Greater neutrophilia inSiat1ΔP1 andSiat1-null animals. Peripheral blood was collected from mice in the absence of treatment (resting, A) or after the following administrations: TG 4h, 4 hours after intraperitoneal 4% (wt/vol) thioglycollate (B); EPI 30m, 30 minutes after intravenous 0.25 mg/kg epinephrine (C); GCSF 30m, 30 minutes after intravenous G-CSF administration (D-E). Collected blood was analyzed by flow cytometry after the lysis of red blood cells, and the granulocyte population (7/4⁺/1A8⁺) was calculated by taking the percentage of the appropriate PE-7/4 and FITC-1A8 events against total events for each flow cytometric acquisition. *Mutant animal data points at which statistically significant differences with corresponding WT have been reached. (A) n = 21, WT; n = 21, Siat1ΔP1; n = 4, Siat1-null. (B) n = 4, WT; n = 4 Siat1ΔP1; P = .003. (C) n = 4, WT; n = 4, Siat1ΔP1; P < .001. (D) n = 8, WT; n = 6 Siat1ΔP1; P < .001. (E) n = 4, WT; n = 4 Siat1-null; P = .03. Error bars indicate 1 standard deviation from the mean of each group.