Vascular permeability alterations induced by arsenic.
The impact of arsenic on the integrity of blood vessels in vivo via in situ exposure (local injection) of arsenic was investigated. Vascular permeability changes were evaluated by means of the Evans blue assay and the India ink tracer techniques. Rats were intravenously injected with Evans blue followed by intradermal injections of various doses of sodium arsenite on the back skins of the animals. Evans blue at different time points was extracted and assayed as indices of vascular leakage. Skin at various time point injection sites was sampled for arsenic measurement via graphite furnace atomic absorption spectroscopy. Our time course study with Evans blue technique demonstrated a biphasic pattern of vascular permeability change: an early phase of permeability reduction and a later phase of permeability promotion at all dose levels tested. The India ink tracer technique also demonstrated a time-correlated increase in vascular labelling in the tissues examined, signifying an increase in vascular leakage with time. Moreover, we found that despite an early increase in tissue arsenic content at time of injection, tissue arsenic declined rapidly and returned to near control levels after 30-60 min. Thus, an inverse correlation between tissue arsenic content and the extent of vascular permeability was apparent. This study provides the first demonstration that in situ exposure to arsenic will produce vascular dysfunction (vascular leakage) in vivo.
Chen
Shih-Chieh
SC
Department of Anatomy, Kaohsiung Medical University, Taiwan, ROC.
Tsai
Ming-Hsien
MH
Wang
Hsiu-Jen
HJ
Yu
Hsin-Su
HS
Chang
Louis W
LW
D000818:Animals; D018053:Arsenites / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity*; D002199:Capillary Permeability / Q000187:drug effects*; D004396:Coloring Agents / Q000008:administration & dosage; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity*; D005070:Evans Blue / Q000008:administration & dosage; D007271:Injections, Intradermal; D007275:Injections, Intravenous; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D017670:Sodium Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity*; D013054:Spectrophotometry, Atomic
D018053:Arsenites; D004396:Coloring Agents; D004791:Enzyme Inhibitors; D017670:Sodium Compounds; D005070:Evans Blue; C017947:sodium arsenite