NO concentration in the periendothelial area of the femoral artery of the dog measured in vivo.
.NO concentration was measured in the periendothelial area of the femoral artery by Malinski's porphyrinic .NO sensor in seven anaesthetized dogs. The basal concentration was 154.2 +/- 5.6 nM and two-minute intraarterial infusions of acetylcholine (3-4 micrograms/ml/min) or bradykinin (30-40 ng/ml/min) increased this value significantly to 204.3 +/- 16.4 and 266.5 +/- 16.4 nM (P < 0.01), respectively. Inhibition of .NO synthase by L-NAME (50 mg/kg) declined the basal .NO concentration only to 137.2 +/- 3.3 nM (P < 0.01). Subsequent administration of acetylcholine and bradykinin attenuated significantly the increase in .NO concentration. Surprisingly, both agonists still induced a significant increase of .NO concentration by 125.3 +/- 8.3 and 156.6 +/- 26.9 nM, respectively (P < 0.01). One of the possible explanations may be that besides arginine-citrulline plus the .NO pathway other sources of .NO could be involved in the high level of .NO after .NO synthase blockade by L-NAME.
Gerová
M
M
Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Bratislava, Slovak Republic.
Mesaros
S
S
Kristek
F
F
Kittová
M
M
Malinski
T
T
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D015374:Biosensing Techniques; D001920:Bradykinin / Q000494:pharmacology; D004285:Dogs; D004730:Endothelium, Vascular / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005263:Femoral Artery / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000032:analysis*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III
D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; D000109:Acetylcholine; D001920:Bradykinin; D019331:NG-Nitroarginine Methyl Ester