Low nitric oxide values associated with low levels of zinc and high levels of cardiac necrosis markers detected in the plasma of rabbits treated with L-NAME.
Nitric oxide plays a key role as a vasodilating agent and its deficiency is associated with ischemic heart diseases. The aim of this study was to induce biochemical alterations associated with ischemic heart lesions by blocking nitric oxide synthase. L-NAME, a nitric oxide synthase inhibitor, was administered to rabbits and its effects on blood pressure, plasma levels of nitric oxide, zinc and cardiac necrosis markers, heart histology, and electrocardiographic profile were examined. L-NAME administration reduced the nitric oxide levels and consequently increased the diastolic blood pressure. It also caused small areas of myocardial coagulative necrosis, whose dispersed nature made it undetectable by electrocardiograph, and decreased the plasma levels of zinc, which is involved in the enzymatic activities that remove the peroxides damaging the myocardium. This model is proposed for the development of drugs affecting nitric oxide levels with the aim of controlling coronary ischemia.
Department of Pharmacology, Chemotherapy, and Medical Toxicology, Ospedale Niguarda Ca' Granda, Milan, Italy. arnaldo.pinelli@unimi.it
A
A
Pinelli
S
S
Trivulzio
L
L
Tomasoni
B
B
Bertolini
S
S
Brenna
E
E
Bonacina
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004562:Electrocardiography / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D008297:Male; D009206:Myocardium / Q000473:pathology*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology*; D009336:Necrosis; D009569:Nitric Oxide / Q000097:blood*; D011817:Rabbits; D015032:Zinc / Q000097:blood*
D004791:Enzyme Inhibitors; D009569:Nitric Oxide; D015032:Zinc; D019331:NG-Nitroarginine Methyl Ester