Elias Salzer, Zahra Gorgin Karaji, Marina van Doeselaar, Marianna A Tryfonidou, Keita Ito
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引用次数: 0
Abstract
Purpose: Limited nutrient transport is hypothesized to be involved in intervertebral disc (IVD) degeneration. It is widely recognized that the dominant mode of transport of small molecules such as glucose is via diffusion, rather than convection. However, recent findings suggest a role for convection-induced by fast (motion-related) and slow (diurnal) dynamic loading in molecular transport of even such small solutes. The aim of this study was to investigate whether fluid exchange induced by simulated physiological loading (composed of both fast cyclic or slower diurnal loading) can influence the molecular transport of a small molecule through the cartilage endplate (CEP) into the nucleus pulposus (NP) of IVDs.
Methods: The molecular transport of fluorescein through the CEP and into the NP was studied in a bovine CEP/NP explant model and loading was applied by an axial compression bioreactor. The loaded explants (convection and diffusion) were compared to unloaded explants (diffusion alone).
Results: In the initial 24 h, there were no differences between loaded and unloaded explants, indicating that convection did not enhance molecular transport of small solutes over diffusion alone. Notably, after 48 h which corresponds to two complete diurnal cycles of tissue compression, fluid exudation/imbibing and redistribution, the fluorescein concentration was significantly increased in the top and bottom layer of the explant, when compared to the unloaded explant.
Conclusions: Slower diurnal cyclic compression of the IVD might enhance the transport of small molecules into the IVD although it could not be discerned whether this was due to diffusion/convection or a combination.
期刊介绍:
"European Spine Journal" is a publication founded in response to the increasing trend toward specialization in spinal surgery and spinal pathology in general. The Journal is devoted to all spine related disciplines, including functional and surgical anatomy of the spine, biomechanics and pathophysiology, diagnostic procedures, and neurology, surgery and outcomes. The aim of "European Spine Journal" is to support the further development of highly innovative spine treatments including but not restricted to surgery and to provide an integrated and balanced view of diagnostic, research and treatment procedures as well as outcomes that will enhance effective collaboration among specialists worldwide. The “European Spine Journal” also participates in education by means of videos, interactive meetings and the endorsement of educative efforts.
Official publication of EUROSPINE, The Spine Society of Europe