Expression of cell volume-regulated kinase h-sgk in pancreatic tissue

Transcript levels of the human serine/ threonine kinase h-sgk have been fou nd to be highest in pancreas. In the present study, localization and regula tion of h-sgk transcription in pancreatic tissue were elucidated. As was ap parent from radioactive in situ hybridization, most pancreatic acinar cells expressed high levels of h-sgk mRNA. h-sgk mRNA-positive cells were also f ound in ductal epithelia but not in pancreatic islets. In biopsy specimens from patients with pancreatitis, h-sgk mRNA levels were decreased in acinar cells but abundant in numerous mononuclear interstitial cells within areas of pancreatic necrosis and fibrosis. As shown by Northern blotting, h-sgk transcription in DAN-G pancreatic tumor cells is upregulated by osmotic cel l shrinkage, serum, phorbol esters (phorbol 12,13-didecanoate), and Ca2+ io nophore A-23187 and decreased by staurosporine and cAMP. In conclusion, h-s gk transcription is regulated not only by cell volume but also by serum, pr otein kinase C stimulation, cAMP, and increase of intracellular Ca2+ activi ty. The kinase may participate not only in normal function of exocrine panc reas but also in fibrosing pancreatitis.