Biomaterials used in some biomedical devices are exposed to flow of physiological fluids. The flow-induced forces may influence the morphological and the biochemical responses of adhering cells. The objective of this work is to examine the capacity of a mechanical stress to cause changes in cell/substratum and cell/cell interactions via the second messenger cAMP pathway (cyclic Adenosine Monophosphate). Cyclic AMP is known to modulate cell shape, cell adhesion and intercellular communication in static conditions. A specially designed flow chamber was used to analyze the responses of mouse 3T3 fibroblasts spread on biocompatible substrata and submitted to controlled shear stresses. A 1.1-Pa shear stress induced: cell rounding, disruption of vitronectin receptors clusters and clustering of connexins 43 at cell-cell apposition points. These cell responses were cAMP-dependent. These investigations should help provide a better understanding of the early biochemical events triggered by mechanical forces.
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Acc Chem Res
January 2025
Department of Chemistry, Ben-Gurion University of the Negev, Be'er Sheva 84105, Israel.
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Department of Aqualife Medicine, Chonnam National University, Yeosu, Republic of Korea.
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Department of Molecular, Cellular, and Developmental Biology; University of Michigan; Ann Arbor, Michigan, 48109; USA.
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