Background: Angiotensin II (ANG II) is a stress hormone and its level
dramatically increases in the stomach during stress. In addition, it generates
reactive oxygen species (ROS) with cellular damage and inflammation. So the
aim of this study is to evaluate the mechanism of losartan and enalapril in the
prevention of stress-induced gastric ulcer through their action on mucosal
prostaglandin (PGs) and antioxidant enzymes and compare between them.
Methods: Thirty- six adult male wistar albino rats weighing 180-200 g were
divided into 6 groups; n= 6. Groups 1, 2, and 3 were received saline (normal
control), losartan (3 mg/kg/day) and enalapril (10 mg/kg/day) i.p respectively
for 4 weeks. Groups 4, 5, and 6 were pretreated with saline (ulcer control),
losartan (3 mg/kg/day) and enalapril (10 mg/kg/day) i.p respectively for 4
weeks duration. On 29th day, group 4, 5 and 6 were submitted to gastric ulcer by
water immersion method, then animals of all groups were sacrificed, stomachs
were excised for gross and microscopic examination and determination of the
mucosal levels of prostaglandin E2 (PGE2), superoxide dismutase (SOD), nitric
(oxide (NO) and catalase (CAT)
Results: Stress produced gastric ulcer and a significant decrease in all measured
gastric parameters compared to normal control group. Pre-treatment of rats with
losartan or enalapril decreased the stress-induced alterations in mucosal
parameters, but only losartan caused a significant increase in CAT activity in
addition
Conclusions: Antagonize the action of ANG II by losartan and enalapril have
preventive advantages in stress-induced gastric ulcer and losartan has better
influence as it has an additional effect on CAT activity