[Effects of omega-3 acids on endothelium-dependent relaxation in hypercholesterolemic rabbits].
OBJECTIVE
To study the effect of omega-3 fatty acid on endothelium-dependent relaxation, total plasma cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides levels as well as, the malondialdehyde (MDA) content of the LDL particles and arterial wall.


METHODS
Fourteen male rabbits were randomly assigned to hypercholesterolemic and omega-3 groups. The dose of omega-3 fatty acid utilized was 300g/kg/day during 15 days. All rabbits were fed a diet supplemented with cholesterol (0.5%) and coconut oil (2%) for four weeks. At the end of the experiment the animals were killed and the aorta removed for measurement of MDA content and the endothelium-dependent relaxation studies. Total plasma cholesterol, VLDL-cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides was measured by enzymatic kits. MDA was also measured in natives and oxidized LDL and arterial wall.


RESULTS
Cholesterol and VLDL-cholesterol were increased significantly in the omega-3 treated animals. The triglyceride level was significantly reduced (p < 0.05). The MDA content was increased in the LDL particles and in the arterial wall (p < 0.05). Endothelium-dependent relaxation was significantly reduced (p < 0.05).


CONCLUSIONS
Omega-3 fatty acid impairs the endothelium-dependent relaxation when administered to cholesterol fed rabbits, increases the cholesterol and reduces the triglycerides plasma levels. The lipid peroxidation of the LDL particles and arterial wall was increased.
Jorge
P A
PA
Núcleo de Medicina e Cirurgia Experimental, UNICAMP, Campinas.
Neyra
L C
LC
Ozaki
R M
RM
de Almeida
E
E
D000818:Animals; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D015243:Cholesterol, VLDL / Q000097:blood; D004727:Endothelium / Q000187:drug effects* / Q000503:physiopathology; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D006937:Hypercholesterolemia / Q000503:physiopathology*; D009569:Nitric Oxide / Q000502:physiology*; D011817:Rabbits; D014280:Triglycerides / Q000097:blood
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D015243:Cholesterol, VLDL; D015525:Fatty Acids, Omega-3; D014280:Triglycerides; D009569:Nitric Oxide
Efeito dos ácidos graxos ômega-3 sobre o relaxamento-dependente do endotélio em coelhos hipercolesterolêmicos.