Figure 1.

Dose-dependent effect of protein C (PC) on leukocyte recruitment in tumor necrosis factor-α (TNF-α)-stimulated cremaster muscle venules. Leukocyte adhesion (per mm² of surface area), rolling flux fraction (RFF) (percentage), leukocyte rolling velocity (μm/s) in cremaster muscle venules, and intravascular and extravascular leukocytes (per mm² surface area) in cremaster muscles were compared 3 hours after TNF-α stimulation and after intravenous administration of indicated doses of PC or isotonic control solution for 800 U/kg PC (control 800; contains as much human serum albumin as 800 U/kg PC). Adherent leukocytes (A), RFF (B), and rolling velocities (C) in cremaster muscle venules are presented for the different treatment groups. Intravascular (D) and perivascular (E) number of leukocytes were observed in Giemsa-stained cremaster muscle whole mounts obtained after the respective intravital microscopic experiments. The distribution of intravascular and perivascular leukocytes in TNF-α-treated cremaster muscles tissue is additionally illustrated by representative micrographs of cremaster muscle whole mounts of control mice (F), after 100 U/kg (G) and 800 U/kg PC (H). As indicated by arrows in (F–H) the majority of intravascular and extravascular leukocytes are neutrophils. Scale bar for (F–H) is shown in G and represents 50 μm. All values are presented as mean ± SEM from at least three mice per group. Significant differences (*P < 0.05) to control are indicated.