title: Time course of arteriogenesis following femoral artery occlusion in the rabbit.
abstract: OBJECTIVE
  We examined the time course of arteriogenesis (collateral artery growth) after femoral artery ligation and the effect of monocyte chemoattractant protein-1 (MCP-1).
  
  
  METHODS
  New Zealand White rabbits received MCP-1 or phosphate buffered saline (PBS) for a 1-week period, either directly or 3 weeks after femoral artery ligation (non-ischemic model). A control group was studied with intact femoral arteries and another 1 min after acute femoral artery ligation.
  
  
  RESULTS
  Collateral conductance index significantly increased when MCP-1 treatment started directly after femoral artery ligation (acute occlusion: 0.94+/-0.19; without occlusion: 168.56+/-15.99; PBS: 4.10+/-0.48; MCP-1: 33.96+/-1.76 ml/min/100 mmHg). However, delayed onset of treatment 3 weeks after ligation and final study of conductance at 4 weeks showed no significant difference against a 4-week control (PBS: 79.08+/-7.24; MCP-1: 90.03+/-8.73 ml/min/100 mmHg). In these groups increased conductance indices were accompanied by a decrease in the number of visible collateral vessels (from 18 to 36 identifiable vessels at day 7 to about four at 21 days).
  
  
  CONCLUSIONS
  We conclude that the chemokine MCP-1 markedly accelerated collateral artery growth but did not alter its final extent above that reached spontaneously as a function of time. We show thus for the first time that a narrow time window exists for the responsiveness to the arteriogenic actions of MCP-1, a feature that MCP-1 may share with other growth factors. We show furthermore that the spontaneous adaptation by arteriogenesis stops when only about 50% of the vasodilatory reserve of the arterial bed before occlusion are reached. The superiority of few large arterial collaterals in their ability to conduct large amounts of blood flow per unit of pressure as compared to the angiogenic response where large numbers of small vessels are produced with minimal ability to allow mass transport of bulk flow is stressed.
authors.affiliation: Department of Experimental Cardiology, Max-Planck-Institute for Physiological and Clinical Research, Benekestr. 2, D-61231, Bad Nauheim, Germany. ihoefer@kerkhoff.mpg.de
authors.forename: I E
authors.initials: IE
authors.lastname: Hoefer
authors.forename: N
authors.initials: N
authors.lastname: van Royen
authors.forename: I R
authors.initials: IR
authors.lastname: Buschmann
authors.forename: J J
authors.initials: JJ
authors.lastname: Piek
authors.forename: W
authors.initials: W
authors.lastname: Schaper
mesh_terms: D000818:Animals; D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology*; D018932:Chemokine CCL2 / Q000627:therapeutic use*; D003097:Collateral Circulation / Q000187:drug effects*; D004195:Disease Models, Animal; D005263:Femoral Artery / Q000000981:diagnostic imaging; D006439:Hemodynamics / Q000187:drug effects; D006614:Hindlimb / Q000098:blood supply; D008026:Ligation; D008863:Microspheres; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D011817:Rabbits; D011859:Radiography; D011897:Random Allocation; D013997:Time Factors
chemical_list: D018932:Chemokine CCL2