Abstract
The high in vitro radiosensitivity of the mucopolysaccharide matrix of connective tissue was demonstrated by Brinkman and Lamberts in 1961 in experiments involving changes in membrane permeability. Their data revealed that the permeability of a relatively crude, multilayered preparation of connective tissue could be affected by doses as low as 5r. This sensitivity was attributed to a depolymerization of the mucopolysaccharides of the connective tissue in a review by Brinkman of both in vitro and in vivo studies. Changes in permeability in connective tissue membranes as a result of treatment with Ba140sO4 were also noted by Brinkman in this review who suggested that the sensitivity of this matrix might be greatly influenced by small concentrations of Ba140 binding with the mucopolysaccharide molecules themselves. This binding within the macromolecules would greatly decrease the dose necessary to effect depolymerization. Dunstone demonstrated that the alkaline earth series of elements were capable of such binding. The relative affinities for Ca, Sr, and Ba were seen to increase in the order 2 to 3 to 4 and were most apparent in chondroitinsulfate A. The effects of such an increase in permeability in connective tissue membrane might not seem of vital importance. However, if the connective tissue of the aorta and particularly the acid mucopolysaccharide component of this tissue is considered, the consequences become more readily apparent.