Intimal permeability evaluated in a short-term organ culture of diabetic guinea pig aorta

A novel short-term organ culture system was used to evaluate intimal permeability changes by measuring aortic [14C]methylated albumin accumulation. Aortic plugs were removed from the upper thoracic aorta of male guinea pigs and maintained in serum-free media. The accumulation of [14C]albumin in the intimal-medial layer was determined after a 5 h incubation. In preliminary studies, albumin recovered from intimal-injured aortic plugs was significantly greater than those from non-injured plugs. Aortic plugs from streptozotocin-treated guinea pigs, diabetic for 3 weeks, also accumulated significantly more [14C]albumin than plugs from nondiabetic controls. Histological changes were not observed in the aorta of either the diabetic or control group. A strong significant inverse correlation was found between plasma ascorbic acid levels and [14C]-activity recovered from aortic plugs. This study demonstrates a simple and rapid method for assessing aortic permeability changes under a well-defined in vitro system, and suggests that vascular permeability changes in the streptozotocin-diabetic guinea pig may be associated with an ascorbic acid deficit.