Illustration of a pulmonary artery of an animal pre-treated with L-NAME or Saline before IV MNC administration.

<p>Arrows point toward Q tracker labeled MNCs.</p

Details of different behavioral tests and scores.

<p>Details of different behavioral tests and scores.</p

L-NAME inhibits the beneficial effect of MNCs.

<p>(A) Chronic infarct cavity at 28 days after stroke in animals treated with saline or MNCs. Animals at 24 hrs after stroke received saline followed by IV MNCs (10 million cells), or L-NAME followed by IV MNCs (10 million cells), or saline only. Lesion size was reduced by MNCs at 28 days after stroke. However, pre-treatment with L-NAME before MNC infusion abolished this reduction in lesion size (§p<0.05 compared with saline). The lesion size was calculated as a percent of the contralateral cortex N = 8 per group. (B) Neurological deficits serially evaluated after stroke in animals treated with saline IP followed by IV infusion of MNCs or L-NAME IP followed by IV infusion of MNCs. At 28 days, animals treated with saline followed by MNCs showed a significant reduction in deficits compared with animals treated with L-NAME+MNCs or compared with animals treated with saline only (§p<0.05). The x-axis represents the time in days after stroke. Baseline refers to the time point before stroke. N = 8 per group.</p

Changes in Cerebral perfusion.

<p>(A) Perfusion weighted imaging was performed in animals receiving MNC or saline at 24 hrs after MCA occlusion. There was a significant decrease (‡p<0.05) in the mean TTP in the peri-infarct region at 5 minutes after MNC infusion via IA or IV routes of delivery. There was no significant change in TTP in the saline group before and after injection. N = 4 per group. (B) Cerebral perfusion (CP) was monitored with Laser Doppler flowmetry over the peri-infarct area of animals administered MNCs (10 million cells) or saline at 24 hrs after MCA occlusion. CP was expressed after injection as a percentage compared with the baseline pre-injection value. CP increased at 5 minutes after MNC injection. There was no significant change in CP in the saline treated group. N = 6 per group. (C): Time course of changes in cerebral perfusion after IV injection of MNCs (10 million cells), FBCs (10 million), or saline. ‡p<0.05 refers to the MNC group compared to the saline group and §p<0.05 refers to the MNC group compared with the FBC group. There was significant elevation of CP after MNC infusion at 1, 3, 5, 10 and 15 minutes. There was no significant change in CP in the saline or FBC groups. ‘0’ on x-axis represents the time in minutes, just before the injection. N = 6 per group.</p

Experimental design.

<p>Experimental design.</p

Time course of changes in cerebral perfusion after administration of MNCs at 24 hours after stroke.

<p>Changes in cerebral perfusion were measured with LDF over the peri-infarct region. Animals at 24 hrs after stroke were treated with L-NAME or saline 60 min before administration of MNCs IV. A third group of control animals received L-NAME followed by saline IV. §p<0.05 refers to the group pre-treated with saline followed by IV MNCs compared with the group pre-treated with L-NAME followed by MNCs IV. ‘0’ on the x-axis represents the time in minutes, just before the injection. N = 5 per group.</p

Biodistribution of MNC in brain, spleen and lungs after IV administration of MNCs(10 million) at 24 hrs after stroke.

<p>MNCs were labeled with Q-tracker(green). These animals had undergone stroke, 24 hrs later were injected with MNCs IV and then sacrificed 1 hr afterwards. Sections were prepared at 1 hr after injection and counterstained with DAPI (blue). L-NAME was injected via IP 1 hr prior to MNC administration. N = 3 per group. (A): Representative microscopic pictures illustrating MNCs (green+blue) in animals pre-treated with L-NAME (top row) or saline (bottom row). Magnification: 400×. (B): A histogram illustrating the mean number of labeled MNCs per high power field in the brain, spleen, and lungs. Animals were pre-treated with L-NAME before IV injection of MNCs or animals were pre-treated with saline followed by IV injection of MNCs (‡p<0.05).</p

Time course of changes of NO at 24 hours after stroke.

<p>(A): Serum NO levels after saline or MNC (IV or IA) administered at 24 hrs post stroke. §p<0.05 for IA or IV MNC treated groups compared with the saline treated group. Time zero refers to the time right before cell or saline injection. N = 5 per group. (B): Serum NO levels in animals treated with L-NAME administered 60 min before MNC injection IV. §p<0.05 refers to the MNC group compared with the saline group; ‡ p<0.05 refers to the MNC group compared with the L-NAME+MNC group. N = 5 per group.</p