Summary
Hemin is a heme oxygenase-1 (HO-1) inducer which provides endogenous carbon monoxide
known for playing roles in cell proliferation,inflammation or aggregation process.
The objective of the current study was to examine the effect of prophylactic treatment
with hemin in a thrombosis vascular model. Three groups of Wistar rats, control (n=6),
hemin (n=6) and hemin+HO-1 inhibitor (n=6), were used for this study. Hemintreated
animals received hemin (50 mg/kg/d; I.P.) for seven days and HO-1 inhibitor group
received hemin at the same dose and SnPP IX (60 mg/kg/d; I.P.). All animals were exposed
to electric stimulation of the left carotid according to Kawasaki’s procedure to induce
reproducible thrombus formation. The hemin treatment did not induce blood pressure
disturbance. Effects of hemin on vascular thrombosis were quantified by histopathology
and its influence on haemostasis was assessed by measuring prothrombin time (PT),
activated partial thromboplastin time (APTT) and blood parameters at the end of treatment.
The HO-1 mRNA and protein level variation were also checked out. Results showed that
chronic treatment with hemin significantly (p<0.01) reduced the vascular occlusion
degree when compared to control and hemin SnPP groups with 7.2 ± 4.6 vs. 71.1 ± 14.7
and 74.0 ± 8.8%, respectively. Moreover, we observed significant (p<0.05) perturbations
of blood parameters in hemintreated and hemin-SnPP treated rats. Interestingly, hemin
treatment did not significantly increase both PT and APTT. Finally, the HO-1 mRNA
and protein levels were increased in hemintreated carotid artery. In conclusion, hemin
by inducing HO-1 expression may be a preventive agent against clinical disorders associated
to an increased risk of thrombosis events and may limit haemorrhagic risks.
Keywords
Hemin - vascular thrombosis - rat