NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Formation of otoconia in the Japanese red-bellied newt, Cynops pyrrhogasterPre-mated adult female newts and fertilized eggs will be flown on the International Microgravity Laboratory-2 flight, in 1994. One objective of the flight will be to observe the influence of microgravity on the development of the gravity-sensing organs in the inner ear. These organs contain sensory hair cells covered by a layer of dense stones (otoconia). Gravity and linear acceleration exert forces on these masses, leading to excitation of the nerve fibers innervating the hair cells. If the production of the otoliths is regulated to reach an optimal weight, their development might be abnormal in microgravity. Ground-based control experiments are reported describing the developmental sequence in which both the otoliths and their associated sensory epithelium and the semicircular canals appear and develop. Three-dimensional reconstruction of serial sections through the otic vesicle of newt embryos at stages 31 through 58 demonstrate the first appearance, relative position and growth of the otoliths. Reports of experiments in which fertilized frog eggs were flown on a Russian Cosmos mission conclude that the utricular otolith is increased in volume, whereas the saccular otolith maintains normal size, suggesting that at least in the utricle, the weight of the otolith might be regulated.
Document ID
19950029071
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Wiederhold, M. L.
(University of Texas Health Science Center San Antonio, TX, US, United States)
Yamashita, M.
(Institute of Space and Astronautical Science Sagamihara, Japan)
Larsen, K.
(University of Texas Health Science Center San Antonio, TX, US, United States)
Asashima, M.
(Yokohama City University Yokohama, Japan)
Date Acquired
August 16, 2013
Publication Date
August 1, 1994
Publication Information
Publication: Life sciences and space research 25 (1). Gravitational biology; Interdisciplinary Scientific Commission F of the COSPAR Plenary Meeting, 29th, Washington, DC, Aug. 28-Sep. 5, 1992. A95-60632
Volume: 14
Issue: 8
ISSN: 0273-1177
ISBN: 0-08-042485-6
Subject Category
Life Sciences (General)
Accession Number
95A60670
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available