Light and electron microscopic study on the effect of immobilization stress on adrenal cortex of adult rats and possible ameliorative role of vitamin E.

Abstract

Background: Modern society is full of stress. Immobilization stress is a model used in animals to study its effects. Vitamin E is an antioxidant that protects biological membranes from oxidative stress. Objectives: This study aimed to investigate the effects of immobilization stress on the adrenal cortex of rats and the ameliorative effect of vitamin E. Materials and Methods: Forty adult male rats were used in this study and were divided equally into 4 groups. Group I: were divided equally into negative and positive controls. Group II: rats received vitamin E at a dose of 40 I.U/kg by gastric tube for 30 days. Group III: rats subjected to immobilization stress 2 hours /day for 30 days. Group IV: rats subjected to immobilization stress 2 hours /day and received 40 I.U/kg of vitamin E for 30 days. Adrenal sections were histologically prepared and examined. Results: Group II was comparable to group IA. Group III revealed zona glomerulosa (ZG) with loss of normal architecture, zona fasciculata (ZF) with multiple cells containing cytoplasmic vacuolations and darkly stained nuclei. By EM ZG cells appeared with accumulations of lipid droplets and lysosomes, irregular nuclear envelopes and chromatin condensation. ZF cells showed numerous lipid droplets and irregular nuclear envelopes. There were significant increases in the mean area of collagen fibers and mean serum cortisol level. Group IV revealed regression of these changes and increase in the mean count of CD44 +ve cells. Conclusions: Immobilization stress exerted deleterious suprarenal cortical changes and vitamin E had an ameliorative effect.

An Ethanolic Extract of Cucurbita pepo L. Seeds Modifies Neuroendocrine Disruption in Chronic Stressed Rats and Adrenal Expression of Inflammatory Markers and HSP70

“…Many cells in the adrenal glands of CUMS-exposed rats showed deeply stained nuclei, indicating that they underwent apoptosis that was confirmed by caspase-3 immunohistochemical staining. Similar observation was reported by Altayeb and Salem, (2017 ), while they were studying the effect of immobilization stress on adrenal glands of rats. Liu Q. et al (2015) reported that excessive oxidative stress, evident following exposure to CUMS in this study, modifies the expression levels of “apoptosis-related genes” and induces cell apoptosis and degeneration through signaling pathways of Bcl-2, Bax, and caspase-3.…”

“…It was described that upon exposure to physical stress, pain stimuli are transmitted to the hypothalamus, resulting in CRH secretion into the hypophyseal portal system, which increases ACTH secretion and stimulates its receptors in the ZF and ZR to increase cortisol secretion (Patti et al, 2018). The thickened adrenal capsule and trabeculae observed in CUMS-exposed rats were previously reported (El-Desouki et al, 2011;Altayeb and Salem, 2017) as a result of increased collagen synthesis by fibroblasts on exposure to immobilization stress.…”

Table1.XLS

“…Many cells in the adrenal glands of CUMS-exposed rats showed deeply stained nuclei, indicating that they underwent apoptosis that was confirmed by caspase-3 immunohistochemical staining. Similar observation was reported by Altayeb and Salem, (2017), while they were studying the effect of immobilization stress on adrenal glands of rats. Liu Q. et al (2015) reported that excessive oxidative stress, evident following exposure to CUMS in this study, modifies the expression levels of "apoptosis-related genes" and induces cell apoptosis and degeneration through signaling pathways of Bcl-2, Bax, and caspase-3.…”

Amelioration of renal cortex histological alterations by aqueous garlic extract in gentamicin induced renal toxicity in albino rats: a histological and immunohistochemical study

“…(1) -The mean area percentage of collagen fibers deposition in sections stained by Masson's trichrome [21]. (2) The mean area percentage of caspase −3 immunostaining.…”