Our results indicate that, in cerebral arteries,. HU induced an increase in RyR1 expression and VDCC function that potentiated all spontaneous Ca2+ signals.
Author's personal copy Pflugers Arch - Eur J Physiol DOI 10.1007/s00424-013-1387-9
INTEGRATIVE PHYSIOLOGY
Up-regulation of ryanodine receptor expression increases the calcium-induced calcium release and spontaneous calcium signals in cerebral arteries from hindlimb unloaded rats Jean-Luc Morel & Fabrice Dabertrand & Yves Porte & Anne Prevot & Nathalie Macrez
Received: 6 August 2013 / Revised: 2 October 2013 / Accepted: 15 October 2013 # Springer-Verlag Berlin Heidelberg 2013
Abstract Microgravity induces a redistribution of blood volume. Consequently, astronauts' body pressure is modified so that the upright blood pressure gradient is abolished, thereby inducing a modification in cerebral blood pressure. This effect is mimicked in the hindlimb unloaded rat model. After a duration of 8 days of unloading, Ca2+ signals activated by depolarization and inositol-1,4,5-trisphosphate intracellular release were increased in cerebral arteries. In the presence of ryanodine and thapsigargin, the depolarization-induced Ca2+ signals remained increased in hindlimb suspended animals, indicating that Ca2+ influx and Ca 2+ -induced Ca 2+ release mechanism were both
J.-L. Morel and F. Dabertrand had equal participation in this study. J.
