It was a First Class Start which Laid the Basis for a Promising Future Experience from Comparative Studies on Gravity Related Behavior in Animals and Consequences for Future Experiemnts

摘要

The main title was chosen in imitation of the headline of a lecture given by H.S. Wolff at the ESA-Symposium "Life Odyssey" in Maastricht/NL (1999) to contrast his pessimistic view of the science output from biological microgravity studies during the past 25 years with an optimistic view of the author who had the opportunity for studies on the gravity sensory systems of developing vertebrates and insects during the space missions STS-55, STS-84, and STS-90, and who was stimulated by this experience to undertake any effort to extent these studies on the International Space Station ISS. We studied compensatory eye and head movements induced by a lateral roll of the animals, and we found that exposure to both microgravity and hypergravity affect their development. Future studies have to consider long-term exposures to altered gravitational conditions to find answers to two questions, the mechanism of adaptation during exposure, and the degree of residual effects after becoming an adult animal and also after re-entry to 1G-conditions. The main hypothesis on the development of animals in space is that a fertilized egg will be converted to a normal adult animal guided by physiological and morphological set-points which represent the genetic program. In case of developmental retardations or accelerations or otherwide occurring deviations from normal structural and physiological development during specific periods of the embryonic and postembryonic life, these genetically defined supervisors activate readaptive mechanisms which direct the developmental processes towards normality, i.e., stability. Thus, an orbit-stabilized organism will be dramatically disturbed after return to Earth. Because this failure will need support to reach neuronal stability, research has also to consider the analysis of mechanisms which are able to overcome these disturbances. This research will open the door to applications because it forms a bridge to human medicine with its analytical research on control procedures over neuropathological mechanisms.