OBJECTIVETo investigate the effect of rhG-CSF on mobilizing bone marrow-MSCs, re-endothelialization and intima hyperplasia in carotid artery of rabbits post balloon catheter injury.

METHODSRabbits were treated with rhG-CSF (25 microg/kg, twice daily, i.p, n = 35) or saline (n = 32) for 5 days, then, carotid arteries of rabbits were injured by balloon catheter. The number of peripheral MSCs was detected with FACS. The morphology of injured artery was examined with hematoxylin and eosin stain, PCNA was determined with immunohistochemistry.

RESULTS(1) Number of peripheral MSCs was similar at baseline and significantly increased at 24 hours and peaked at 7 days and remained increased till 14 days post rhG-CSF. (2) Significant endothelial cell deletion was evidenced in the control group, while scatter endothelial cells was observed in the rhG-CSF group at 1 week post injury. Two weeks after injury, new endothelial area was significantly higher in rhG-CSF group compared to control group. At 4 weeks post injury, endothelial connection was evidenced and regularly displayed in rhG-CSF treated group. (3) PCNA-positive cells in the tunica intima were significantly lower in rhG-CSF treated rabbits at 7, 14 and 28 days compared that in control rabbits (all P < 0.01).

CONCLUSIONrhG-CSF could mobilize the bone marrow-MSCs and promote re-endothelialization and attenuate intima hyperplasia post balloon catheter injury in carotid arteries of rabbits.