Methods are described for dilating biological conduits by removing elastin and remodeling collagens in the wall of the conduit. Methods include the use of agents that increase the release of endogenous elastase and collagenase in the wall of the conduit, either by cells that are normally present in the wall of the conduit or by inflammatory cells that are attracted to the conduit, thereby providing additional conduit dilation. Methods also include the use of agents that increase conduit wall permeability and expose elastin and collagen fibers. Methods also include removing components of the extracellular matrix of arteries and veins leading to an inhibition of intimal hyperplasia in the wall of the vessels by decreasing biomechanical stimuli directed toward the cells in the wall of the vessel. Methods further include the use of agent that degrade microfibers, in addition to elastin, in order to decrease the resynthesis of elastin. Methods also include the use of agent that stabilize the diameter of aneurysmal arteries by blocking cell surface receptors in the wall of the aneurysmal artery that are important in the recruitment of inflammatory cells.