The Effects of Simulated Spaceflight Conditions on the Mucin Lining of the Mouse Uterine Tube

Abstract

To determine the effects of spaceflight on the mucin layer of uterine tubes, female mice were subjected to simulated microgravity and/or low dose rate radiation (LDR). Astronaut age-appropriate (6 months old), female C57BL/6 mice were exposed to anti-orthostatic tail suspension (AOS) for up 21 days to model the unloading, fluid shift, and physiological stress aspects of the microgravity component. Subsets of mice were also exposed to whole-body, gamma-irradiation (0.04Gy at 0.01cGy/h) using 57Co plates to simulate the LDR radiation component. Mice were then euthanized at 1, 4 or 9 months after the 21 day simulation. Tissues were harvested and quantitatively analyzed for mucin production by measuring the mucin layer thickness of the isthmus, ampulla, and infundibulum regions of the uterine tubes. Analyses conducted indicate that there were no significant reductions in the isthmus and ampulla sections across all treatment groups at the 1, 4, and 9 month time samples. The infundibulum section showed significant reductions at 4 and 9 months post treatment, but there was not a significant change in thickness at 1 month post treatment. These data indicate that both simulated microgravity and radiation exposure cause a thinning of the mucin layer in the infundibulum region of the uterine tube, but do not cause significant morphological changes in the isthmus and ampulla sections of the tube