Hypertension III: Flow-Induced Vascular Remodeling

Dr. D. Tulis (0444) NOS and growth factors

Robert M.K.W. Lee
rmkwlee@fhs.mcmaster.ca

This is an interesting study. I have 2 questions.
1. In the second order arteries, you have noted that there was a decrease in cell density in the media after 7 days, and you suggested that nuclear polyploidy may be involved. I agree with that. However, in your discussion, you went on to suggest that these cells may proceed to divide. Since you did not study these vessels after 7 days, we do not know if this will indeed take place. Assuming that hyperplasia occurs in the ileal artery, as you have shown, and hypertrophy occurs in the second-order artery, does it mean that the smooth muscle cells in these two arteries were different, or different growth factors were involved?
2. You did not show your connective tissue results. In the increase you have found, can you distinguish whether the increase was due to collagen or elastin, or both?

Thu Dec 10