Calbindin-D28k immunoreactivity in the mice thoracic spinal cord after space flight

Abstract

The aim of the work was to analyse changes in the location and morphological characteristics of calbindin (CB)-immunoreactive (IR) neurons of the thoracic spinal cord of C57BL/6N male mice after completion of a 30-day space flight on board the BION-M1 biosatellite (Russia, 2013). Space flight induced multidirectional changes of the number and morphological parameters of CB-positive neurons. The number of IR neurons increased in laminae I (from 10 to 17 neurons per section), II (from 42 to 67 cells per section) and IX (from two neurons per segment to two neurons per section), but CB disappeared in neurons of lamina VIII. Weightlessness did not affect the number of CB-IR neurons in laminae III–V and VII, including preganglionic sympathetic neurons. The cross-sectional area of CB-IR neurons decreased in lamina II and VII (group of partition cells) and increased in laminae III–V and IX. After a space flight, few very large neurons with long dendrites appeared in lamina IV. The results obtained give evidence about substantial changes in the calcium buffer system and imbalance of different groups of CB-IR neurons due to reduction of afferent information under microgravity.

Gene-Metabolite Network Linked to Inhibited Bioenergetics in Association With Spaceflight-Induced Loss of Male Mouse Quadriceps Muscle

“…Finally, our first priority was to rapidly extract the tissues to minimize the freezethaw cycle. Nevertheless, previous studies reported insignificant change in body weights of mice after space travels (32,33) and after exposing mice to hindlimb unloading on the ground. (34) Altered calcium usage, decreased mtDNA CNs, and inhibited tricarboxylic acid (TCA) cycles are likely to converge to impair mitochondrial function, because these are causally related to essential cellular metabolism.…”

“…Finally, our first priority was to rapidly extract the tissues to minimize the freeze‐thaw cycle. Nevertheless, previous studies reported insignificant change in body weights of mice after space travels ( 32,33 ) and after exposing mice to hindlimb unloading on the ground. ( 34 )…”

Neuronal nitric oxide synthase and calbindin expression in sympathetic preganglionic neurons following capsaicin treatment

“…We also observed changes in the number of CB‐immunoreactive (IR) neurons in the SC after a sensory deficit was induced by space flight (Porseva et al, 2015, 2017). The neurotoxic effect of capsaicin is also explained by the excessive intracellular accumulation of Ca 2+ and Na + ions, which leads to protease activation and cell death (Hwang et al, 2021; Jin et al, 2005).…”

“…Numerous unmyelinated fibers run from one half of the gray matter of the SC to the other, especially dorsally from the central canal, where the CAA is located. This suggests an integrative and coordinating function, which is typical for the entire intermediate zone of the SC with interneurons of different functional specifications (Deuchars et al, 2005; Porseva et al, 2015).…”