tetracycline and Arteriosclerosis

Topics: Aged; Arteriosclerosis; Cell Wall; Cryptococcus; Edetic Acid; Endocarditis, Bacterial; Escherichia coli; Haemophilus Infections; Humans; Immunity, Cellular; L Forms; Lysostaphin; Male; Penicillins; Protoplasts; Salmonella; Sepsis; Spheroplasts; Stomatitis; Streptococcal Infections; Tetracycline; Thrombophlebitis; Urinary Tract Infections; Whipple Disease

Topics: Animals; Arteriosclerosis; Chlorophyll; Hematoporphyrin Derivative; Hematoporphyrin Photoradiation; Hematoporphyrins; Humans; In Vitro Techniques; Laser Therapy; Male; Photochemotherapy; Rabbits; Radiation-Sensitizing Agents; Tetracycline

Tetracycline has been shown to collect selectively in atherosclerotic plaque and is a known photosensitizing agent. To determine if tetracycline enhances the photoablative effects of the ultraviolet xenon-fluorine excimer laser, the authors exposed four cadaveric aortic samples to tetracycline and four to only normal saline. Ninety-three sites in the samples were subjected to laser energy and analyzed with light microscopy for crater depth and width and for degree of thermal injury. Forty-three of the sites were histologically normal, and 50 were atherosclerotic. Crater depth did not differ significantly in atherosclerotic and normal sites not exposed to tetracycline. Atherosclerotic sites exposed to tetracycline showed significantly deeper craters compared with those in normal, exposed sites. The effects of tetracycline exposure and histologic characteristics (normal vs atherosclerotic) on crater width and thermal injury were independent and additive. When the excimer laser is used for treatment, tetracycline can definitely enhance atherosclerotic plaque ablation.

Topics: Aorta; Arteriosclerosis; Humans; In Vitro Techniques; Laser Therapy; Tetracycline

Topics: Animals; Aorta; Arteriosclerosis; Humans; In Vitro Techniques; Laser Therapy; Photochemotherapy; Rabbits; Tetracycline

Tetracycline is an antibiotic that absorbs ultraviolet light at 355 nm and preferentially binds to atherosclerotic plaque both in vitro and in vivo. Tetracycline-treated human cadaveric aorta was compared with untreated aorta using several techniques: absorptive spectrophotometry, which demonstrated a distinct absorptive peak at 355 nm in tetracycline-treated plaque that was absent in treated normal vessel; ultraviolet microscopy, which showed that treated atheroma acquired the characteristic fluorescence of tetracycline under ultraviolet light; and tissue uptake of radiolabeled tetracycline, which showed 4-fold greater uptake by atheroma than by normal vessel. In addition, intravenous tetracycline administered to patients undergoing vascular surgery demonstrated characteristic fluorescence in surgically excised diseased arteries. Because of tetracycline's unique properties, we exposed tetracycline-treated and untreated aorta to ultraviolet laser radiation at a wavelength of 355 nm. We found enhanced ablation of tetracycline-treated atheroma compared with untreated atheroma. The plaque ablation caused by ultraviolet laser radiation was twice as extensive in tetracycline-treated vs nontreated plaque (2.2 +/- 0.25 mm vs 1.3 +/- 0.55 mm, p less than 0.017). This study demonstrates the potential of tetracycline plaque enhancement for the selective destruction of atheroma by ultraviolet laser radiation.

Topics: Absorption; Aortic Diseases; Arteriosclerosis; Humans; In Vitro Techniques; Laser Therapy; Lasers; Radioligand Assay; Spectrometry, Fluorescence; Tetracycline; Ultraviolet Rays

Topics: Anti-Bacterial Agents; Arteriosclerosis; Cardiac Surgical Procedures; Cross Infection; Humans; Intestinal Diseases; Lung Diseases; Postoperative Complications; Staphylococcal Infections; Streptomycin; Surgical Wound Infection; Tetracycline; Vascular Surgical Procedures

Topics: Aorta; Arteriosclerosis; Histocytochemistry; Humans; Microradiography; Microscopy, Fluorescence; Tetracycline