Age-related arterial calcification in rats

In man, i) arteries calcify with age and ii) age-linked arterial calcificat ion is amplified by vascular pathology such as hypertension or arterioscler osis. Age-linked arterial calcification has a bad prognosis but drugs to pr event it are lacking. This is partially due to the lack of appropriate anim al models. This paper looks at the extent to which arteries calcify with ag e in the rat and whether hypertension or arteriosclerosis amplifies such ca lcification. Total calcium levels were determined by acid digestion and fla me spectrophotometry and intracellular calcium levels ([Ca2+](i)) by the in tracellular calcium-sensitive dye, fura-2. Arteries contained up to 5 times more calcium than other soft tissues. Arteries progressively calcified wit h age whereas other soft tissues did not. Accumulation of calcium with age was essentially extracellular. Hypertension had no effect on age-related ar terial calcification. Calcification of the same order as in man was produce d in a rat model of arteriosclerosis (vitamin D plus nicotine treatment). I n conclusion, as in man, age-linked, organ-specific arterial calcification does occur in rats but its intensity is far less. Arterial calcification of a similar degree to that observed in man can be obtained in rats by hyperv itaminosis D plus nicotine.