The link between androgens and coronary artery disease remains elusive
and the possible mechanisms that may relate testosterone to the
development of cardiovascular diseases have not been well established
yet. This study was designed to clarify the effect of testosterone hormone
on lipid peroxidation and oxidants-antioxidant balance in rat myocardial
tissue. Forty male albino rats included in this study were divided into 4
equal groups. Group (1) served as control rats and the other three groups
were subjected to castration. One week after castration, group (2) rats
were injected with solvent, group (3) rats received Lm. testosterone enant
thate 10 mg/kg once weekly and group (4) received Lm.daily injections of
vitamin E (alpha-tocopherol) in a dose of 20 mg/kg/day. All injections
were continued for 4 weeks then all rats were scarificed by decapitation
and the hearts were obtained and prepared for the estimation of lipid peroxides
as thiobarbituric acid reactive substance (TBARS), nitrite concentration,
glutathione (GSH), glutathione perox-idase (GSH-PX) activity and
vitamin E (alpha tocopherol). TBARS and nitrites concentrations were significantly
higher in the myocardial tissue extract of group (2) than group
(1) rats while GSH and GSH-PX were significantly lower, indicating that
castration put the rat myocardial tissue under oxidative stress. However,
in group (3) and group (4), TSARS and nitrites were significantly lower
and GSH and GSH-PX activity were significantly higher than group (2), indicating
that testosterone replacement therapy as well as vitamin E therapy
protected the castrated rats from the oxidative stress and restored
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the oxidant- antioxidant balance in rat myocardial tissue. It could be concluded
that testosterone may have a role in preserving oxidantantioxidant
balance in myocardial tissue of albino rats and this may be
one of the mechanisms that could explain a suggested cardioprotective
role of testosterone. |
