Evaluation of the nitric oxide production in rat renal artery smooth muscle cells culture exposed to radiocontrast agents.
BACKGROUND
Radiocontrast agents (RC), substances largely used in diagnostic procedures, present the nephrotoxicity as one of its major side effects, which could be due to an altered synthesis of vasodilators. The aim of the present study was to evaluate the nitric oxide (NO) production in rat renal artery smooth muscle cells primary culture (rVSMC) exposed to RC.


METHODS
The cells were treated for 72 hours with mannitol at 10% (MT10; 600 mOsm/kg H2O) or 35% (MT35; 2100 mOsm/kg H2O), with the nonionic iobitridol (IBT), the low-osmolality ioxaglate (IXG), the high-osmolality ioxitalamate (IXT), the nonionic, iso-osmolar iodixanol (IDX), and with lipopolysaccharide (LPS). We determined the NO and osmolality in the cell culture media and the cellular viability.


RESULTS
By the Griess and chemiluminescence methods, the NO was not different in MT10 and IDX, but decreased in MT35, IBT, IXG, and IXT when compared with the control; it was increased in LPS and also decreased in all RC+LPS when compared with LPS. MT35, IXT, and IXT+LPS decreased the cellular viability, and the media osmolality was increased in MT35 and IXT compared with the control.


CONCLUSIONS
The RC (except IDX) significantly reduced NO in rVSMC, which was more pronounced after IXT treatment (57.3%). This was not related to the reduced cell viability (15.8%) or to its high osmolality, because in MT35, with similar osmolality as IXT, NO decreased only 11.0% relatively to the control. Neither the media osmolality nor the cell viability was altered by IXG or IBT. The decreased NO could explain the vasoconstriction and, therefore, the acute renal failure by RC.
Ribeiro
Luciane
L
Nephrology and Emergency Division, Universidade Federal de São Paulo, Escola Paulista de Medicina, São Paulo, Brazil.
de Assunção e Silva
Fábio
F
Kurihara
Rose Saemi
RS
Schor
Nestor
N
Mieko
Elisa
E
Higa
Suemitsu
S
D000818:Animals; D002478:Cells, Cultured; D003287:Contrast Media / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D007472:Iohexol / Q000031:analogs & derivatives* / Q000494:pharmacology*; D007483:Iothalamic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D007485:Ioxaglic Acid / Q000494:pharmacology; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012077:Renal Artery / Q000166:cytology*; D014283:Triiodobenzoic Acids / Q000494:pharmacology
D003287:Contrast Media; D014283:Triiodobenzoic Acids; D007483:Iothalamic Acid; C093233:iobitridol; D009569:Nitric Oxide; D007472:Iohexol; C002587:ioxitalamic acid; C044834:iodixanol; D007485:Ioxaglic Acid