Sleep deprivation enhances peripheral serotonin secretion to regulate the large follicle steroidogenesis of rats.

Abstract Objective Sleep deprivation (SD) leads to the disturbance of the estrous cycle. Serotonin, the levels of which increase with SD, has been shown to inhibit luteinizing hormone production and the receptor has been found in the follicles. In this study, the serotonin effect on preovulatory follicular steroidogenesis is investigated and the underlying mechanisms are elucidated. Materials and methods Female rats were subjected to SD for a time span of 1–4 days using the dish-over-water-method with a Rechtschaffen apparatus. Serum estradiol and serotonin concentrations were assessed; thereafter, they were evaluated with the effect of serotonin on the estradiol production and steroidogenic acute regulatory (StAR) protein expression in a serum-free culture system. Preovulatory follicles were dissected mechanically from the ovaries of 21-day-old rats, which induced follicle growth, and cultured for 24 hours with or without recombinant human follicle-stimulating hormone (FSH) in the presence or absence of serotonin. Results SD, led to a significant decrease in serum estradiol concentrations, while serotonin concentrations were significantly elevated (all p Conclusion These findings suggest that decreased serum estradiol concentrations in SD rats may be the result of serotonin-related inhibition of estradiol production and decreased large follicle expression of StAR protein.