Oestrous cyclicity disruption in Wistar rats subjected to partial sleep deprivation

Abstract

Background: Chronic partial sleep deprivation continues to be a global problem. Studies have shown that oestrous cyclicity is disrupted by total sleep deprivation. The relationship between partial sleep deprivation – the predominant form of sleep deprivation in the current global society – and the oestrous pattern remains elusive. This study examined oestrous cycle patterns of rats subjected to partial sleep deprivation.

Methods: Thirty female Wistar rats were divided into control and Sleep-Deprived (SD) groups of fifteen rats each. Oestrous patterns were monitored for two weeks before sleep deprivation and throughout the study. Sleep deprivation was induced using the modified multiple platform method. Five animals were sacrificed under thiopental anaesthesia during proestrus on days 7, 14 and 21. The ovaries, uteri and adrenal glands were examined. Data were compared using t-test at p<0.05.

Results: Proestrus and oestrus frequencies reduced in the SD groups; metestrus frequency increased in the 7 days and 14 days SD and diestrus frequency increased in 21 days SD group. Cycle lengths increased in the 14 days and 21days SD groups. The SD groups had inflammation of ovary and uterus, as well as adrenal medulla hyperplasia.

Conclusion: Partial sleep deprivation reduces frequencies of phases characterized by sexual activity and ovulation while increasing cycle lengths in Wistar rats. Thus, adequate sleep is important for women who are trying to get pregnant.

Keywords: Sleep deprivation, Oestrous cycle, Adrenal medulla, rats