1: Atherosclerosis. 2001 Mar;155(1):113-22. 

Heme oxygenase-1 attenuates vascular remodeling following balloon injury in rat
carotid arteries.

Tulis DA, Durante W, Peyton KJ, Evans AJ, Schafer AI.

Department of Medicine, Baylor College of Medicine, 6550 Fannin, SM MS 1423,
Houston, TX 77030, USA.

The heme oxygenase-1 (HO-1) system of heme catabolism has been proposed to exert
protective actions upon the cardiovascular system. This investigation examined
the influence of HO-1 induction on vascular remodeling following arterial
injury. Rats were subjected to left carotid artery (LCA) balloon injury
following pre-treatment with either vehicle, the HO-1 inducer hemin (50 mg/kg,
SC), or concomitant treatment with hemin and the HO-1 inhibitor
tin-protoporphyrin IX (SnPP-IX; 50 micromol/kg, IP). Animals were injected daily
for 14 days post-injury, after which animals were sacrificed and tissues
obtained. Western blot analyses revealed vascular HO-1 induction after 2 and 16
days of hemin treatment. Positive immunostaining for HO-1 was detected in the
endothelial and adventitial layers following 48 h of hemin treatment and
positive medial staining for HO-1 after 16 days of hemin treatment. The injured
LCA of hemin-treated animals demonstrated significantly attenuated neointimal
(NI) area (-57%), NI thickness (-58%), and NI area/medial wall area ratio (-40%)
compared to the injured LCA of vehicle controls. The cross-sectional medial wall
areas of both LCA and uninjured RCA were also significantly reduced in the
hemin-treated animals. SnPP-IX treatment, however, completely restored the NI
area, NI thickness, NI area/medial wall area ratio, and partially restored the
medial wall area towards control levels. These results directly implicate HO-1
and the products of heme catabolism in attenuating the arterial response to
injury and ensuing vascular wall remodeling.

PMID: 11223432 [PubMed - indexed for MEDLINE]