Studies of Hard and Soft Tissue Elemental Compositions in Mice and Rats Subjected to Simulated Microgravity

Microgravity has profound effects on skeletal as well as other body systems. To investigate the effect of microgravity, we have used a NASA validated Hind‐limb suspension (HLS) animal model of simulated weightlessness. Groups of mice and rats were subjected to hind limb suspension between 1 and 14 days while the control groups were maintained without suspension for the same duration. To study the effect of diet, some groups of animals were fed on a special diet with defined composition. At term, the animals were sacrificed and the tibia, femur, and skull bones were collected. In addition, soft tissues from pancreas and muscles were also collected. All of the bones and tissues samples were analyzed for elemental analysis using Energy Dispersive Spectroscopy (EDS) equipped on a Scanning Electron Microscope (SEM). In the EDS, 10–20 keV electrons bombarded the samples and a Si (Li) detector measured K‐, L‐ and M‐shell x‐rays. Independently, X‐Ray Fluorescence (XRF) provided the data for comparison and normali...