Inhibition of L-arginine transport by reactive oxygen species in rat anococcygeus muscle.
The effect of L-arginine on nitrergic transmission and its alteration with reactive oxygen species (ROS) were investigated. L-arginine potentiated the relaxation response induced by electrical field stimulation in rat anococygeus muscle. This effect was inhibited by L-lysine, a cationic amino acid using y+ L and y+ transport systems in a similar way with L-arginine. The neutral amino acid L-leucine, which uses only y+ L system as a transport mechanism, inhibited this potentiation at only low frequency stimulation. Electrolysis of the physiological solution did not change the responses to electrical field stimulation, but inhibited the potentiation elicited by L-arginine that was prevented in the presence of mannitol and N-acetyl-L-cysteine. In conclusion, L-arginine is transported via y+ system predominantly to potentiate the relaxation response to nitrergic nerve stimulation in rat anococcygeus muscle. ROS, primarily hydroxyl radicals inhibited L-arginine-induced potentiation probably by interacting with the y+ amino acid transport system.
Durlu
N Tugba
NT
Department of Pharmacology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey.
Ismailoglu
U Burcin
UB
Sahin-Erdemli
Inci
I
D001003:Anal Canal / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001120:Arginine / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects / Q000502:physiology; D066298:In Vitro Techniques; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism* / Q000494:pharmacology
D017382:Reactive Oxygen Species; D001120:Arginine