Acid sensing in renal epithelial cells

Division of Nephrology, UCSF, 513 Parnassus Avenue, Box 0532, San Francisco, California 94143-0532, USA.
Journal of Clinical Investigation (Impact Factor: 13.22). 01/2005; 114(12):1696-9. DOI: 10.1172/JCI23864
Source: PubMed


The kidney adjusts net acid excretion to match production with exquisite precision, despite little or no change in the plasma bicarbonate concentration. The acid-sensing pathway that signals the kidney to increase acid secretion involves activation of the proto-oncogene c-Src. A new study in this issue shows that proline-rich tyrosine kinase 2 (Pyk2) is responsible for acid-induced activation of c-Src and is essential for acid sensing in renal epithelial cells. The findings implicate a broader role for Pyk2 in acid-base homeostasis in bone and other tissues beyond the kidney.

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