Diverse relaxation responses of canine large and small conductive coronary arteries to glyceryl trinitrate and nitric oxide on the one hand and to 8-bromoguanosine 3':5' cyclic monophosphate on the other.
Glyceryl trinitrate (GTN) and nitric oxide (NO) preferentially relaxed the large (2 mm in diameter) conductive coronary artery (CCA) of the dog, while 8-bromoguanosine 3':5' cyclic monophosphate preferentially relaxed the small one (0.6 mm in diameter). Neither L-cysteine nor L-acetylcysteine affected GTN-induced relaxation in small- and large-CCA. These results indicate that not different biotransformation of GTN to NO, but a process or processes operative between activation of guanylate cyclase and that of cyclic GMP-dependent protein kinase seems to be responsible for the preferential dilatation of large-CCA.
Kitagawa
T
T
Department of Pharmacology, Niigata University School of Medicine, Japan.
Ishibashi
T
T
Imai
S
S
D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D001711:Biotransformation; D003331:Coronary Vessels / Q000187:drug effects; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000494:pharmacology; D017869:Cyclic GMP-Dependent Protein Kinases / Q000378:metabolism; D003545:Cysteine / Q000494:pharmacology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D016166:Free Radical Scavengers / Q000494:pharmacology; D006162:Guanylate Cyclase / Q000378:metabolism; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009569:Nitric Oxide / Q000378:metabolism / Q000494:pharmacology*; D005996:Nitroglycerin / Q000493:pharmacokinetics / Q000494:pharmacology*; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000493:pharmacokinetics / Q000494:pharmacology*
D016166:Free Radical Scavengers; D014665:Vasodilator Agents; C016276:8-bromocyclic GMP; D009569:Nitric Oxide; D017869:Cyclic GMP-Dependent Protein Kinases; D006162:Guanylate Cyclase; D005996:Nitroglycerin; D006152:Cyclic GMP; D003545:Cysteine; D000111:Acetylcysteine