TY - JOUR
T1 - The role of volume-sensitive ion transport systems in regulation of epithelial transport
AU - Hoffmann, Else Kay
AU - Schettino, T
AU - Marshall, W S
N1 - Keywords: Animals; Eels; Epithelium; Ion Transport
PY - 2007
Y1 - 2007
N2 - This review focuses on using the knowledge on volume-sensitive transport systems in Ehrlich ascites tumour cells and NIH-3T3 cells to elucidate osmotic regulation of salt transport in epithelia. Using the intestine of the European eel (Anguilla anguilla) (an absorptive epithelium of the type described in the renal cortex thick ascending limb (cTAL)) we have focused on the role of swelling-activated K+- and anion-conductive pathways in response to hypotonicity, and on the role of the apical (luminal) Na+-K+-2Cl- cotransporter (NKCC2) in the response to hypertonicity. The shrinkage-induced activation of NKCC2 involves an interaction between the cytoskeleton and protein phosphorylation events via PKC and myosin light chain kinase (MLCK). Killifish (Fundulus heteroclitus) opercular epithelium is a Cl(-)-secreting epithelium of the type described in exocrine glands, having a CFTR channel on the apical side and the Na+/K+ ATPase, NKCC1 and a K+ channel on the basolateral side. Osmotic control of Cl- secretion across the operculum epithelium includes: (i) hyperosmotic shrinkage activation of NKCC1 via PKC, MLCK, p38, OSR1 and SPAK; (ii) deactivation of NKCC by hypotonic cell swelling and a protein phosphatase, and (iii) a protein tyrosine kinase acting on the focal adhesion kinase (FAK) to set levels of NKCC activity.
AB - This review focuses on using the knowledge on volume-sensitive transport systems in Ehrlich ascites tumour cells and NIH-3T3 cells to elucidate osmotic regulation of salt transport in epithelia. Using the intestine of the European eel (Anguilla anguilla) (an absorptive epithelium of the type described in the renal cortex thick ascending limb (cTAL)) we have focused on the role of swelling-activated K+- and anion-conductive pathways in response to hypotonicity, and on the role of the apical (luminal) Na+-K+-2Cl- cotransporter (NKCC2) in the response to hypertonicity. The shrinkage-induced activation of NKCC2 involves an interaction between the cytoskeleton and protein phosphorylation events via PKC and myosin light chain kinase (MLCK). Killifish (Fundulus heteroclitus) opercular epithelium is a Cl(-)-secreting epithelium of the type described in exocrine glands, having a CFTR channel on the apical side and the Na+/K+ ATPase, NKCC1 and a K+ channel on the basolateral side. Osmotic control of Cl- secretion across the operculum epithelium includes: (i) hyperosmotic shrinkage activation of NKCC1 via PKC, MLCK, p38, OSR1 and SPAK; (ii) deactivation of NKCC by hypotonic cell swelling and a protein phosphatase, and (iii) a protein tyrosine kinase acting on the focal adhesion kinase (FAK) to set levels of NKCC activity.
U2 - 10.1016/j.cbpa.2006.11.023
DO - 10.1016/j.cbpa.2006.11.023
M3 - Journal article
C2 - 17289411
SN - 1095-6433
VL - 148
SP - 29
EP - 43
JO - Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology
JF - Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology
IS - 1
ER -