Chronic stress influences nociceptive sensitivity of female rats in an estrous cycle-dependent manner.

Abstract

Exposure to chronic stress can influence nociception and further induce hyperalgesia. Whether stress modulation of pain in female animals occurs in an estrous cycle-specific manner is still unclear. We profiled the changes in nociception (thermal, mechanical, formalin-evoked acute and inflammatory pain) of female Sprague-Dawley rats after treatment with chronic unpredictable mild stress (CUMS) and investigated whether these changes occur in an estrous cycle-dependent manner. The results showed that CUMS female rats exhibited a lower mechanical withdrawal threshold in proestrus and estrus, a longer formalin-evoked licking time in metestrus and diestrus, but no changes in the latency time on the tail-flick test. The present study findings suggest that chronic stress induces mechanical and formalin-evoked acute hyperalgesia of female rats in an estrous cycle-dependent manner.SUMMARYOur studies showed that chronic stress increased nociceptive sensitivity of female rats. Furthermore females had different stress-induced pain responses in different estrous phases: mechanical hyperalgesia in proestrus and estrus, formalin-evoked acute hyperalgesia in metestrus and diestrus.

• Authors: Chun-Xiao Yang, Yi Wang, Qi Lu, Yan-Na Lian, Enoch Odame Anto, Ying Zhang, Wei Wang
• Journal: Stress (Amsterdam, Netherlands) (Stress) Vol. 23 Issue 4 Pg. 386-392 (07 2020) ISSN: 1607-8888 [Electronic] England
• PMID: 31672079 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Topics

• Animals
• Estrous Cycle
• Female
• Hyperalgesia (chemically induced)
• Nociception
• Rats
• Rats, Sprague-Dawley
• Stress, Psychological