Activation of the MAPKs ERK1/2 by cell swelling in turbot hepatocytes.

Background Information: Activation of MAPKs (mitogen-activated protein kinases), in particular ERK1/2 (extracellular-signal-regulated kinase 1/2), has been reported to take place in a large variety of cell types after hypo-osmotic cell swelling. Depending on cell type, ERK1/2 phosphorylation can then serve or not the RVD (regulatory volume decrease) process. The present study investigates ERK1/2 activation after aniso-osmotic stimulations in turbot hepatocytes and the potential link between phosphorylation of these proteins and RVD.

Involvement of respiratory chain in the regulatory volume decrease process in turbot hepatocytes.

Regulatory volume decrease (RVD) constitutes a fundamental process that turbot (Scophthalmus maximus) hepatocytes are able to perform when exposed to hypo-osmotic stress. RVD is an integrative mechanism that involves various elements of the cellular machinery. Among others, ATP is an essential protagonist: released following hypo-osmotic shock, it acts as an auto/paracrine factor to trigger other signalling events.