Collateral arterial development and renal function in experimental renal hypertension: preliminary observations

Collateral circulation in stenosis or occlusion of the renal artery

The abdominal angiograms of 381 patients were critically reexamined for the existence of collateral circulation in cases of renal artery stenosis or occlusion. Typical renal artery stenosis was found in 39 patients; among these, 17 had a collateral circulation, which was extrarenal in 15 and intrarenal in two. Collateral circulation involving the lumbar arteries was most common. In two patients a collateral circulation was established via the inferior mesenteric artery.

Collateral circulation after renal artery occlusion in the rat

We used angiographic and microsphere methods to evaluate the anatomic and functional features of renal collateral circulation in the rat. By the microsphere method, renal parenchymal blood flow was less than 1% of control 1 hour after occlusion of the main renal artery; 2.8% of control 1-2 weeks after arterial occlusion; and 1% of control 4-9 weeks after occlusion. Radiographic observations during chronic occlusion revealed numerous collateral vessels to the kidney. These vessels readily filled with angiographic contrast medium but the intrarenal circulation did not visualize. We conclude that collateral circulation to renal parenchyma is negligible after acute or chronic occlusion of the main renal artery in the rat. The rich anatomic plexus of collateral vessels has no functional significance and is unable to preserve viability of the parenchyma.

Collateral vessel formation: isolation of a transferable factor promoting a vascular response

Collateral vessel formation to the kidney was induced by renal artery stenosis or embolization in six dogs. Extracts from control and collateral-forming kidneys were assessed for their ability to promote a vascular response in the hamster cheekpouch. The highly significant response evoked by particulate and soluble fractions of cytoplasm from collateral-forming kidneys suggests a humoral element in collateral vessel formation.

Renal parenchymal tolerance to artery occlusion: a time and damage study in rats developing collateral circulation

Images