Vasorelaxant and antiaggregatory actions of the nitroxyl donor isopropylamine NONOate are maintained in hypercholesterolemia.
Am J Physiol Heart Circ Physiol
; 301(4): H1405-14, 2011 Oct.
Article
em En
| MEDLINE
| ID: mdl-21803947
ABSTRACT
Nitroxyl (HNO) displays pharmacological and therapeutic actions distinct from those of its redox sibling nitric oxide (NO(â¢)). It remains unclear, however, whether the vasoprotective actions of HNO are preserved in disease. The ability of the HNO donor isopropylamine NONOate (IPA/NO) to induce vasorelaxation, its susceptibility to tolerance development, and antiaggregatory actions were compared with those of a clinically used NO(â¢) donor, glyceryl trinitrate (GTN), in hypercholesterolemic mice. The vasorelaxant and antiaggregatory properties of IPA/NO and GTN were examined in isolated carotid arteries and washed platelets, respectively, from male C57BL/6J mice [wild-type (WT)] maintained on either a normal diet (WT-ND) or high fat diet (WT-HFD; 7 wk) as well as apolipoprotein E-deficient mice maintained on a HFD (ApoE(-/-)-HFD; 7 wk). In WT-ND mice, IPA/NO (0.1-30 µmol/l) induced concentration-dependent vasorelaxation and inhibition of collagen (30 µg/ml)-stimulated platelet aggregation, which was predominantly soluble guanylyl cyclase/cGMP dependent. Compared with WT-HFD mice, ApoE(-/-)-HFD mice displayed an increase in total plasma cholesterol levels (P < 0.001), vascular (P < 0.05) and platelet (P < 0.05) superoxide (O(2)(·-)) production, and reduced endogenous NO(â¢) bioavailability (P < 0.001). Vasorelaxant responses to both IPA/NO and GTN were preserved in hypercholesterolemia, whereas vascular tolerance developed to GTN (P < 0.001) but not to IPA/NO. The ability of IPA/NO (3 µmol/l) to inhibit platelet aggregation was preserved in hypercholesterolemia, whereas the actions of GTN (100 µmol/l) were abolished. In conclusion, the vasoprotective effects of IPA/NO were maintained in hypercholesterolemia and, thus, HNO donors may represent future novel treatments for vascular diseases.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Limite:
Animals
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article