Effect of contrast media on vascular smooth muscle cells.
OBJECTIVE
In order to alleviate the adverse effects of contrast media (CMs) on the vascular system, the role of Ca2+ in the viability of vascular smooth muscle cells (VSMCs) was investigated.


METHODS
VSMCs were obtained from swine thoracic aorta. The number of VSMCs was counted under a microscope using the trypan blue dye-exclusion method 24 h after culture in RPMI containing physiological saline (SAL) as control, iothalamate (IOT), or iohexol (IOH) at 10% by volume with CaCl2 added at 0 to 2.0 mmol/l. Free Ca2+ in the above media was measured using an ion-selective electrode.


RESULTS
Free Ca2+ was 0.4 to 1.5 mmol/l with ionic IOT and 0.4 to 1.8 mmol/l with non-ionic IOH as well as with control. The ratio of viable cells grown in the presence of CMs to those grown in the control was optimal at approximately 0.60 near 1 mmol/l Ca2+ and decreased markedly to 0.00 at 1.5 mmol/l Ca2+ in the presence of IOT and to 0.39 at 1.8 mmol/l Ca2+ in the presence of IOH, while the ratios decreased gradually to 0.28 in the presence of IOT and 0.53 in the presence of IOH at 0.4 mmol/l Ca2+.


CONCLUSIONS
Ionic IOT is more cytotoxic to VSMCs than non-ionic IOH. However, the cytotoxicity was minimal and similar between both CMs at 1 mmol/l Ca2+ in accordance with the sodium-calcium balance.
Takatsuki
H
H
Department of Biological and Chemical Engineering, Gunma University, Kiryu, Gunma Japan.
Furukawa
T
T
Liu
Y
Y
Hirano
K
K
Yoshikoshi
A
A
Sakanishi
A
A
D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology; D002118:Calcium / Q000502:physiology; D015220:Calcium Channels / Q000633:toxicity*; D002478:Cells, Cultured; D003287:Contrast Media / Q000633:toxicity*; D007472:Iohexol / Q000633:toxicity; D007483:Iothalamic Acid / Q000633:toxicity; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects*; D013552:Swine
D015220:Calcium Channels; D003287:Contrast Media; D007483:Iothalamic Acid; D007472:Iohexol; D002118:Calcium