Knochenstoffwechsel in der Schwerelosigkeit – Mechanismen und Maßnahmen gegen den Verlust von Knochenmasse

Der Verlust von Knochenmasse im All stellt ein bekanntes Problem mit bedenklichem Ausmaß für Langzeitmissionen dar. Um den Verlust von Knochenmasse zu verhindern und geeignete Gegenmaßnahmen einzusetzen, ist das Verständnis der physiologischen Ursachen absolut unerlässlich. Die Flüssigkeitsverschiebung als früheste Theorie, die mechanische Anpassung des Knochens an veränderte Umgebungsbedingen sowie hormonelle und nutritive Einflüsse stellen wichtige Bereiche der Ursachenforschung dar. Der folgende Artikel gibt eine kurze Übersicht über die Inhalte dieser Theorien und betrachtet ihre aktuelle Bedeutung für die Entwicklung von Maßnahmen zur Verhinderung des Verlustes von Knochenmasse im All.

The loss of bone mass in space is a known problem with an alarming extent for long-term missions. The understanding of the physiological causes is absolutely essential in order to prevent the loss of bone mass and to employ appropriate countermeasures. Fluid shifts as the earliest theory, mechanical adaptation of bone to altered environmental conditions, hormonal and nutritional factors, are important areas of causal research. The following article gives a brief overview of the contents of these theories and considers its current importance for the development of measures preventing the loss of bone mass in space.

Key words

bone loss - weightlessness - physiological causes - countermeasures

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