Glycosaminoglycans in the aorta of six animal species: A chemical and morphological comparison of their topographical distribution

Abstract

The glycosaminoglycans (GAG) from healthy aortic segments of male and female rats, pigs, cattle, rabbits, horses and chickens are identified chemically and partly located histologically, the following being the main findings made: 1. (1) The amount of glycosaminoglycans increases in the order in which the species are arranged above and is about 3 mg uronic acid/g dry defatted weight in the rat and about 7 mg in the chicken. 2. (2) From the aortic arch to the abdominal aorta the total amount of glycosaminoglycans in the rat, pig, rabbit and chicken decreases continuously. This is caused by a reduction of the chondroitin sulfates. 3. (3) Absolute concentrations of hyaluronic acid, heparan sulfate, dermatan sulfate and chondroitin-6-sulfate are species dependent. 4. (4) The glycosaminoglycans, in particular those which are strongly acidic, are histologically located in the intima and inner media. 5. (5) No functional relationship can be shown to exist between the elastic fibers and the glycosaminoglycans. When the six species investigated are arranged in a possible order of susceptibility to spontaneous and experimental arteriosclerosis — if any such order can as yet be set up at all — it seems that with increasing amounts of GAG in the healthy wall, the susceptibility of the aorta to sclerotic changes increases. However there is no recognizable connection with the absolute or relative amounts of any of the glycosaminoglycan fractions investigated.