Decreased blood flow significantly increased cross-sectional intimal area compared to increased flow at 2 weeks (0.11 vs 0.06 mm2, p<0.01) after arterial injury in rats.
Does altered blood flow affect the development of intimal hyperplasia after arterial injury in rats?
Reduced blood flow increases early neointimal hyperplasia following arterial injury in a rat model, suggesting flow dynamics play a key role in vascular remodeling.
Absolute Event Rate: 0.11% vs 0.06%
p-value: p=<0.01
This study examined the effects of blood flow on intimal hyperplasia after balloon catheter injury of the rat common carotid artery. Flow was altered by ligation of the opposite common carotid artery (increased flow) or of the ipsilateral internal carotid artery (decreased flow). Blood flow decreased by 35% in the low-flow group and increased by 29% in the high-flow group. Similar changes in mean velocity were observed. Cross-sectional intimal area was significantly greater in the low- than the high-flow group at 2 weeks (0.11 +/- 0.01 versus 0.06 +/- 0.01 mm2, p less than 0.01) and 4 weeks (0.17 +/- 0.02 versus 0.12 +/- 0.01 mm2, p = 0.01) but not at 1 or 8 weeks. Smooth muscle cell proliferation rates (thymidine labeling indexes) were not different in high- and low-flow groups at 2 days and at 1 and 4 weeks. Matrix accumulation at 2 and 4 weeks was the same in both groups. Mature neointima did not respond to changes in flow; when vessel ligation was delayed until 2 months after injury, there was no effect on neointimal area. These data indicate that early neointimal hyperplasia is increased when flow is reduced, possibly because of alteration of smooth muscle cell migration.
Kohler et al. (Sat,) conducted a other in intimal hyperplasia after arterial injury. Decreased blood flow (ligation of ipsilateral internal carotid artery) vs. Increased blood flow (ligation of opposite common carotid artery) was evaluated on Cross-sectional intimal area at 2 weeks (p=<0.01). Decreased blood flow significantly increased cross-sectional intimal area compared to increased flow at 2 weeks (0.11 vs 0.06 mm2, p<0.01) after arterial injury in rats.