Collateral arterial formation. Lymph draining ischemic kidneys contains a neovascular stimulating agent of high...

An agent has been identified in lymph from rat kidneys rendered ischemic by partial renal artery occlusion that induces a striking neovascular response in a hamster cheek-pouch assay system. The factor has a high molecular weight, cannot be identified in lymph from normal kidneys, and is associated with a marked increase in vascularity and in endothelial cell turnover in the cheek pouch employed for assay. This factor may play an important role in the production of the collateral arterial circulation found in the presence of renal artery stenosis and renal ischemia.