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NASA NTRS · 20040087686

Effects of microgravity on vestibular development and function in rats: genetics and environment

Ronca, A. E.·Fritzsch, B.·Alberts, J. R.·Bruce, L. L.
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Abstract

Our anatomical and behavioral studies of embryonic rats that developed in microgravity suggest that the vestibular sensory system, like the visual system, has genetically mediated processes of development that establish crude connections between the periphery and the brain. Environmental stimuli also regulate connection formation including terminal branch formation and fine-tuning of synaptic contacts. Axons of vestibular sensory neurons from gravistatic as well as linear acceleration receptors reach their targets in both microgravity and normal gravity, suggesting that this is a genetically regulated component of development. However, microgravity exposure delays the development of terminal branches and synapses in gravistatic but not linear acceleration-sensitive neurons and also produces behavioral changes. These latter changes reflect environmentally controlled processes of development.

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mannedshort durationNon-NASA CenterFlight ExperimentReviewNASA Experiment Number 9303031 1/2NASA Experiment Number 9303003STS-66 Shuttle ProjectReview, TutorialNASA Discipline Developmental BiologySTS-70 Shuttle ProjectNASA Experiment Number 9303031 2/2WeightlessnessVestibule/anatomy & histology/embryology/growth & development/physiologySpace FlightGravity Perception/physiologyAxons/physiologySupport, U.S. Gov't, P.H.SRatsFemaleFetus/physiologyHair Cells/anatomy & histology/embryology/growth & development/physiologySupport, U.S. Gov't, Non-P.H.SSynapses/physiologyPregnancyBehavior, Animal/physiologyAnimals

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Ronca, A. E., Fritzsch, B., Alberts, J. R., Bruce, L. L.. 2000-09-01. Effects of microgravity on vestibular development and function in rats: genetics and environment. https://ntrs.nasa.gov/citations/20040087686

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