Beschreibung:
<jats:title>Abstract</jats:title>
<jats:p>Recent studies support the hypothesis that macrophages are not only essential for efficient immune responses, but are also regulators of local tissue electrolyte composition and hence arterial hypertension. Blockade of this macrophage-dependent regulatory axis resulted in skin electrolyte accumulation and blood pressure increase. Based on the observation that macrophages accumulate in skin tissue of rats fed under high salt diet conditions, the question arose whether macrophages actively migrate to sites of high sodium storage. We therefore investigated the migratory behavior of RAW264.7 macrophages, murine bone marrow-derived macrophages and murine peritoneal macrophages toward different NaCl gradients, showing that NaCl may act as a chemotactic stimulus per se. We also assessed the reorganization of the actin cytoskeleton, a potential NaCl-induced chemokine CCL2 production and the role of the osmoprotective transcription factor TonEBP in salt-dependent chemotaxis. Although the underlying mechanism remains unidentified, we propose that salt-dependent chemotaxis might be an important functional feature of macrophages within the context of excess salt clearance in vivo.</jats:p>