The Histomorphometric and Histological Evaluation of Renal Cortex in Response to Sleep Disturbance in Adult Male Rat

Background: Sleep disturbance affects kidney structure reflected in functional derangement causing renal diseases; this occurs through sympathetic system activation and inflammation. Changes in the renal vascular bed affect the renal corpuscle-related structures such as the glomerular area, and urine space, in addition to the kidney tubular apparatus. Sleep deprivation or sleep interruption differ in their effect on systolic blood pressure causing renal tissue changes that predispose to chronic kidney disease (CKD). Aim of the study: The study aims to evaluate the effect of sleep disturbance on histological changes of renal tissue in control and experiment groups. Patients and methods: An experimental study on a sample of thirty adult male albino Rats, was divided into three groups (10 animals per group). The control group had a normal sleep rhythm which was 12 hours in the dark and 12 hours in light. Group A:  at 12 hours light and 12 hours dark with the production of a flashlight at three-time intervals, every 2 hours, during their sleep period, while Group B includes rats that were exposed to a reduction in sleep time by continuous flashlight stimulation for 7 hours per day, during their sleep period. Then, the kidneys were dissected and prepared for histological evaluation and quantification. The experiment lasted for 14 days for all groups, and the study was performed during the period between the 1st of January 2023 to the 1st of August 2023 in the anatomy department in  Al- Nahrain Medical College. Results: This study showed the effect of sleep disturbance patterns (sleep reduction, and sleep interruption) by light stimulation in adult male rats on cortical renal tubules and cortical vessels. A prominent dilatation in cortical renal tubules with the presence of cortical hemorrhagic areas and cortical necrosis with inflammatory cell infiltration was seen to be associated with sleep deprivation prominently. Histological changes of renal corpuscular areas, glomerular tuft area, and renal space area showed significant variations in sleep disturbance groups, in a p-value ≤ 0.05. Conclusions: Changes in sleep patterns indicate the importance of sleep in maintaining renal cortical tissue structural integrity by its effect on local hemodynamics of cortical vessels that ultimately affect the structure and area of the renal corpuscles. Sleep deprivation represents a powerful factor for renal cortical changes that lead to corpuscular and tubular damage.