The effect of L-arginine on neointimal proliferation and artery remodeling on an iliac artery lesion caused by a balloon catheter in hypercholesterolemic rabbits.
OBJECTIVE
It has been implied that neointimal proliferation and remodeling are the major causes of restenosis. The objective of this study is to assess the effect of orally administered L-arginine on these two factors in hypercholesterolemic rabbits that had suffered an injury to their iliac arteries caused by a catheter balloon.


METHODS
The study included nineteen rabbits that were divided in two groups: control (CG) and arginine (AG). There were 19 arteries studied from the control group and 17 in the arginine group. The animals were placed on a 2% hypercholesterolemic diet for 15 days and then submitted to a balloon angioplasty in order to produce a lesion in their iliac arteries. Next, the AG animals were given a 1g/kg/day oral dose of a L-arginine solution. The animals were sacrificed 15 days after the angioplasty procedure and histological artery sections were prepared, stained and fixed. The ratio between the neointimal area (in mm(2)) and the media layer (in mm(2)) was used to represent lesion development. In order to determine remodeling, the ratio between the total area of the medial portion of the vessel (greater balloon contact) and the total area of the reference segment of the vessel (less balloon contact) was used.


RESULTS
Mean neointimal thickness (NI/M) was 0.8151+/-0.2201 in CG and 0.3296+/-0.1133 in AG. Remodeling patterns for the two groups studied were similar.


CONCLUSIONS
In the experimental model used, L-arginine was able to reduce intimal tissue thickness in hypercholesterolemic rabbits but did not act on artery remodeling.
Knopfholz
José
J
Pontifícia Universidade Católica do Paraná, Curitiba, PR, Brazil. jknopfholz@hotmail.com
Précoma
Dalton B
DB
Brofman
Paulo Roberto S
PR
Bier
Gabriela Elisete
GE
da Silva
Ruy Fernando Kuenzer C
RF
Silva
Anna Paula Kuchnir
AP
Lemos
Ana Carolina
AC
Silva
Priscila de Oliveira
Pde O
de Moraes
Jacqueline Dompsin
JD
D000800:Angioplasty, Balloon / Q000009:adverse effects*; D000818:Animals; D001120:Arginine / Q000494:pharmacology*; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000187:drug effects; D006937:Hypercholesterolemia; D007083:Iliac Artery / Q000187:drug effects / Q000293:injuries* / Q000473:pathology; D008297:Male; D011817:Rabbits; D017539:Tunica Intima / Q000187:drug effects* / Q000473:pathology
D001120:Arginine