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Updated: Jul 7, 2026
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Optical Sectioning and Visualization of the Intervertebral Disc from Embryonic Development to Degeneration
Published on: July 8, 2021
Aquaporin expression in the human intervertebral disc.
S M Richardson1, R Knowles, D Marples
1Tissue Injury and Repair Group, School of Clinical and Laboratory Sciences, Faculty of Medical and Human Sciences, The University of Manchester, Manchester M13 9PT, UK.
Journal of Molecular Histology
|February 6, 2008
Summary
Human intervertebral disc (IVD) cells express aquaporins (AQPs) 1 and 3, similar to articular chondrocytes. Expression decreases in the outer annulus fibrosus, suggesting adaptation to mechanical and osmotic changes.
Area of Science:
- Biochemistry
- Cell Biology
- Biophysics
Background:
- The human intervertebral disc (IVD) nucleus pulposus (NP) is a hyperosmotic tissue under dynamic compressive loads.
- Chondrocyte-like cells in the NP must regulate cell volume and extracellular matrix metabolism.
- Aquaporins (AQPs), transmembrane water and solute transporters, are expressed in articular cartilage chondrocytes.
Purpose of the Study:
- To investigate the expression of aquaporins 1, 2, and 3 in human IVD cells using immunohistochemistry.
- To compare the AQP expression profile of IVD cells with that of articular chondrocytes.
Main Methods:
- Immunohistochemistry was used to detect aquaporins 1, 2, and 3.
- Human IVD tissues were analyzed, examining cells from the nucleus pulposus (NP) and inner and outer annulus fibrosus (AF).
Main Results:
- Aquaporins 1 and 3 were expressed by cells in the NP and inner AF.
- Outer AF cells showed no AQP-1 expression and minimal AQP-3 expression.
- All cells analyzed were negative for AQP-2 expression.
Conclusions:
- Human NP cells share phenotypic similarities with articular chondrocytes, potentially due to comparable tissue osmolarity and mechanobiology.
- Decreased AQP expression from NP to outer AF suggests cellular adaptation to regional differences in mechanobiology, osmolarity, and hydration.
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