Cerebral embolization in rats induced by red blood cells treated with hypertonic X-ray contrast medium.
OBJECTIVE
Hypertonic X-ray contrast media induce morphologic changes in red blood cells (RBCs) and reduce their deformability when measured in vitro. This study investigated whether RBCs treated with hypertonic contrast media could induce circulatory as well as metabolic disturbances in vivo.


METHODS
Autologous blood was mixed with an equal volume of meglumine diatrizoate (306 mgI/mL); 50 microliters of this mixture was infused into the left internal carotid artery of rats 2 minutes after mixing. Five minutes after infusion, the cerebral blood flow was determined using iodo[14C]antipyrine. 31P-magnetic resonance spectroscopy (MRS), 1H-MRS and 1H-magnetic resonance imaging (MRI) of the brain were performed before and after infusion of the mixture to study changes in energy metabolites and the integrity of the blood-brain barrier (BBB), as well as the development of edema.


RESULTS
The blood flow decreased by 70% to 80% in the left cerebral cortex and caudate-putamen. 31P-MRS and 1H-MRS demonstrated derangement of oxidative phosphorylation. 1H-MRI demonstrated instant destruction of the BBB and gradual progress of edema in the left hemisphere.


CONCLUSIONS
These results indicate that intracarotid infusion of RBCs treated with hypertonic contrast medium can induce embolization and subsequent ischemic damage to the brain.
Miyazawa
T
T
Nihon Schering K.K., Research Department, Osaka, Japan.
Murayama
C
C
Yamanaka
T
T
Fritz-Zieroth
B
B
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001812:Blood-Brain Barrier; D001921:Brain / Q000378:metabolism; D002560:Cerebrovascular Circulation; D003974:Diatrizoate Meglumine / Q000633:toxicity*; D004912:Erythrocytes / Q000187:drug effects* / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D006982:Hypertonic Solutions; D002542:Intracranial Embolism and Thrombosis / Q000097:blood / Q000139:chemically induced* / Q000378:metabolism / Q000503:physiopathology; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010710:Phosphates / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D006982:Hypertonic Solutions; D007773:Lactates; D010710:Phosphates; D019344:Lactic Acid; D003974:Diatrizoate Meglumine; D000255:Adenosine Triphosphate