DIE BEDEUTUNG DER ARTERIENWÜLSTE FÜR DEN BLUTKREISLAUF

Abstract

Arterial swellings or rings at the origin of arterial branches and protruding into the lumen of the vessel are noted in all classes of vertebrates. In most animals they are composed largely of smooth muscle, but in cyclostomata those at the origin of aortic branches are cartilaginous in character. The cells of this chondroic tissue are scanty, flattened, branched cells which may be of myogenic origin. The muscular rings can contract. The chondroic rings cannot contract, but because of their protrusion into the lumen of the aorta seem to allow only blood from the central part of the aortic stream to enter the vessel.