Calcium activation in vascular smooth musclh by incubation of vessels in elevated fructose and glucose

A high fructose diet has been demonstrated to induce hypertension in seven animal models. We tested the acule effects of fructose and glucos incubations on vascular reactivity by measuring isometric force of aorti tissue in isolated tissue baths. Aortic rings (endothelium intact) fror Sprague-Dawley rats were incubated in physiological salt solution containin glucose (40 mM) or fructose (20 or 40 rnM) for 6 hours. Both treatments increased the contractile response to phenylephrine (10^-7 M) when compared to control vessels. A similar augmentation was observed in the contractile response to the calcium channel agonist (Bay K 8644) indicating calcium activation induced by fructose or glucose incubation. An agonist inducedsmooth muscle oscillation was also noted in elucose or fructose incubated vessels. The relaxation response 10 acelylcholine was not significantly altered in vessels incubated in fructose or glucose. We conclude tlKit calcium channel activation in vascular smooth muscle by iructose or glucose incubation may contribute to the high blood pressure in this model.