These therapeutics could be used to both stop bone loss or stimulate the generation of bone
material while the crew member is in flight.
ADF-Otolith studies how the absence of gravity during the body's formative stage affects basic
neural function in an effort to isolate the major influences on the neurovestibular system, the
system that allows us to control our eye movement, balance, and coordination.
RESULTS
ADF-OTOLITH
The inner ear bones of the embryos developed in microgravity appear to be larger than those
found in the controls that remained on Earth. There are some indications that the fan-shaped
arrangement of receptor cells may also be altered under the influence of microgravity.
Conclusive data from this investigation is pending further analysis (Increment 4 One Year
Postflight Report).
ADF-SKELETAL
No spaceflight effects were observed for osteocalcin levels in the day 12 embryos, based on
bone matrix stating. Since osteocalcin reflects the degree of bone mineralization, this would
suggest that mineralization is not affected in an older embryo. However, direct mineralization
quantitative studies have not been reported for day 7 and day 12 embryos, which should
provide definitive evidence for whether osteocalcin-associated processes are affected.
The second finding was that the spaceflight embryos on the spinning carousel or stationary
carousel had a reduced level of collagen-synthesizing activity as compared to the ground
control specimens, although the sample size was small. If this trend is validated, it would
suggest that spaceflight has a component that can affect collagen synthesis that is not
correctable by an applied 1 g force. These insights might be important for the development of
appropriate countermeasures for space travel. (Increment 4 One Year Postflight Report). Due to
the limited number of samples, statistical analysis was never completed and therefore the work
was not publishable.
These investigations are complete and all results are published.
Scanning electron micrographs of fused otoconial stones from embryonic day 12 quail embryos. Three saccule stones
are shown, one each from an embryo raised from fertilization in 0g (left), 1g flight (middle), and 2g laboratory
centrifugation (right). J. David Dickman image.