ALLOXAN DIABETES ALTERS THE RABBIT TRANSARTERIAL WALL OXYGEN GRADIENT

Purpose: Atherosclerotic vascular occlusive disease is the most common complication of diabetes mellitus and accounts for 75% of deaths in d iabetic patients. Determining the initiator and continuing stimulus fo r the cellular events in the formation of atheroslerotic lesions in di abetic patients could lead to the prevention of this common and deadly complication. Diabetes-induced arterial wall hypoxia is proposed as a n initiator and continuing stimulus for atherosclerotic vascular occlu sive disease. Methods: Transarterial wall oxygen gradient measurements were performed on the infrarenal aorta with an oxygen microelectrode 14 to 16 weeks after the induction of alloxan diabetes in rabbits. Res ults: Both insulin-treated and untreated alloxan diabetic rabbits reve aled significantly decreased oxygen tensions throughout the arterial w all compared with control rabbits. There was no significant difference in the transarterial wall oxygen gradient between the two groups of d iabetic rabbits. This effect was noted despite no difference in the pa rtial pressure of oxygen in arterial blood or visual evidence of ather osclerotic lesion formation in the three groups. Conclusions: These fi ndings suggest that diabetes induces arterial wall hypoxia independent of insulin therapy and before the formation of atherosclerotic lesion s. Diabetes-induced arterial wall hypoxia may contribute to the format ion of atherosclerotic lesions.