Aim: To evaluate the effect of chronic mild stress (CMS) on the emergence of gastric ulcers and possible modulation by octreotide, a synthetic somatostatin analogue.
Methods: Adult male Wistar rats were subjected to nine different unpredictable random stress procedures for 21 d, a multifactorial interactional animal model for CMS. Octreotide was administered daily for 21 d at two dose levels (50 and 90 μg/kg) before exposure to stress procedure. Macro- and microscopical assessments were made, in addition to quantification of plasma corticosterone and gastric mucosal inflammatory, oxidative stress, and apoptotic biomarkers.
Results: Exposure to CMS elevated plasma corticosterone (28.3 ± 0.6 μg/dL, P = 0.002), an event that was accompanied by gastric lesions (6.4 ± 0.16 mm, P = 0.01) and confirmed histopathologically. Moreover, the insult elevated gastric mucosal lipid peroxides (13 ± 0.5 nmol/g tissue, P = 0.001), tumor necrosis factor-α (3008.6 ± 78.18 pg/g tissue, P < 0.001), prostaglandin E2 (117.1 ± 4.31 pg/g tissue, P = 0.002), and caspase-3 activity (2.4 ± 0.14 OD/mg protein, P = 0.002). Conversely, CMS mitigated interleukin-10 (627.9 ± 12.82 pg/g tissue, P = 0.001). Furthermore, in animals exposed to CMS, octreotide restored plasma corticosterone (61% and 71% from CMS, P = 0.002) at both dose levels. These beneficial effects were associated with a remarkable suppression of gastric lesions (38% and 9% from CMS, P = 0.01) and reversal of derangements in gastric mucosa.
Conclusion: The current investigation provides evidence that exposure to CMS induces gastric ulceration, which was alleviated by administration of octreotide possibly possessing antioxidant, anti-inflammatory, and anti-apoptotic actions.
Keywords: Apoptosis; Chronic mild stress; Gastric ulcer; Histopathology; Inflammation; Octreotide; Oxidative stress.