Similarity between the vasorelaxing activity of dinitrosyl iron cysteine complexes and endothelium-derived relaxing factor.
Dinitrosyl iron complexes with cysteine (DNIC) induced a concentration-dependent relaxation of pre-contracted (norepinephrine, 10(-7) M) de-endothelialized ring segments of rat aorta. The vasodilator response was more similar to acetylcholine (ACh)-induced relaxation in intact aortic rings than to nitric oxide (NO)-induced relaxation. The time course of tone recovery after maximal concentrations (10(-5) M) of DNIC was similar to the time course of tone recovery after endothelium-dependent relaxation induced by ACh, whereas the restoration of tone after NO was much faster. Vessel tone was restored by oxyhemoglobin (10(-5) M) in all cases. The results suggest that DNIC with cysteine may function as endothelium-derived relaxing factor in the vessels.
Vedernikov
Y P
YP
Cardiology Research Center, USSR Academy of Medical Sciences, Moscow.
Mordvintcev
P I
PI
Malenkova
I V
IV
Vanin
A F
AF
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000502:physiology; D003545:Cysteine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004355:Drug Stability; D004730:Endothelium, Vascular / Q000502:physiology; D006454:Hemoglobins / Q000494:pharmacology; D066298:In Vitro Techniques; D007700:Kinetics; D009126:Muscle Relaxation / Q000187:drug effects*; D009129:Muscle Tonus / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000502:physiology; D009569:Nitric Oxide / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D006454:Hemoglobins; C072081:dinitrosyl-iron(II)-cysteine; D009569:Nitric Oxide; D003545:Cysteine; D000109:Acetylcholine