Cineradiographic Analysis of Mouse Postural Response to Alteration of Gravity and Jerk (Gravity Deceleration Rate)

Life

卷:4

Yasuhiro Kumei¹  Priscila S. de Campos²  Jorge L. Zeredo²  Katsuya Hasegawa³ 

[1] Department of Hard Tissue Engineering, Tokyo Medical and Dental University Graduate School, Tokyo 113-8549, Japan;

[2] Graduate Program in Health Sciences and Technology, University of Brasilia, Brasilia 72220-140, DF, Brazil;

[3] JAXA/Institute of Space and Astronautical Science, Sagamihara 252-5210, Japan;

关键词: gravity;    jerk;    parabolic flight;    threshold;    spine;    partial gravity;    reflex;    space;    kinesiology;    cineradiography;   

DOI  :  10.3390/life4020174

来源: DOAJ

【 摘 要 】

The ability to maintain the body relative to the external environment is important for adaptation to altered gravity. However, the physiological limits for adaptation or the disruption of body orientation are not known. In this study, we analyzed postural changes in mice upon exposure to various low gravities. Male C57BL6/J mice(n = 6) were exposed to various gravity-deceleration conditions by customized parabolic flight-maneuvers targeting the partial-gravity levels of 0.60, 0.30, 0.15 and μ g (<0.001 g). Video recordings of postural responses were analyzed frame-by-frame by high-definition cineradiography and with exact instantaneous values of gravity and jerk. As a result, the coordinated extension of the neck, spine and hindlimbs was observed during the initial phase of gravity deceleration. Joint angles widened to 120%–200% of the referenceg level, and the magnitude of the thoracic-curvature stretching was correlated with gravity and jerk, i.e., the gravity deceleration rate. A certain range of jerk facilitated mouse skeletal stretching efficiently, and a jerk of −0.3~−0.4 j (g/s) induced the maximum extensionof the thoracic-curvature. The postural response of animals to low gravity may undergo differential regulation by gravity and jerk.

【 授权许可】

Unknown