Decrease in total fluorescence from human arteries with increasing beta-carotene content

摘要

The influence of $Beta@-carotene content upon the laser induced total fluorescence was evaluated in human arteries in vitro using 30 mw argon laser beam at 488 nm. Experiments showed that the $Beta@-carotene content in normal arteries increases with longer period of incubation in $Beta@-carotene solution. This is consistently associated with a drop in total fluorescence. The arterial absorption at 488 nm resulting from $Beta@-carotene deposition is twice as great as that before incubation causing a decrease of total fluorescence by 48%. These experimental data were highly correlated with theoretical analysis derived using a multi- layer model by introducing a parameter describing the quantity of $Beta@-carotene bound to the arterial tissue (R=0.94). Total fluorescence from 138 samples of various types of atherosclerotic plaques was compared with that from normal arteries which were used as controls. The total fluorescence gradually decreases with longer incubation period in $Beta@- carotene solution. Seventy-nine plaques with surface fissures exhibited obvious reduction in total fluorescence. This study shows that the pretreatment with $Beta@-carotene may enhance the ability of the diagnosis of atherosclerotic plaque from normal artery using total fluorescence intensity.