Mn porphyrins reduce cell adhesion and restore blood flow in vivo. (A-E) TS mice were treated subcutaneously with 1 dose of vehicle or 0.5 mg/kg MnE, followed immediately by 500 ng TNF-α; intravital microscopy was then performed per protocol 2. (A) Intravital microscopy was performed on anesthetized treated TS mice. Representative images of postcapillary venules (20× magnification) from treated TS mice are presented. Leukocyte and RBC adhesion and vaso-occlusion are indicated with arrows. Scale bars, 50 μm. (B-D) Video frames showing vessel segments were used to quantify fluorescence-labeled cell (leukocyte and RBC) adhesion (B-C) and leukocyte rolling flux (D) in all venules and arterioles were recorded, and numbers were averaged among groups of animals. Cell adhesion presented as number of adherent cells per 100 μm vessel length (B), and fluorescence unit (FU) (C). Leukocyte rolling flux presented as number of leukocytes per minute (D). TS mice injected simultaneously with 1 dose of 0.5 mg/kg MnE and TNF-α showed sporadic cell adhesion (B-C) and reduced leukocyte rolling (D) as opposed to the vehicle group. (E) Blood flow in vivo. Percentage of vessels with normal, slow, and no blood flow (occluded vessels) are shown. Average vessel diameter was almost identical (∼21 μm) in all treatment groups. Blood stasis in TS mice treated with 0.5 mg/kg MnE was significantly reduced compared with the vehicle group. Error bars show SEM of 6 different experiments for each treatment group. **P < .01 compared with vehicle treatment regardless of the vessel diameter within the ranges specified.