Jun Kinases Are Rapidly Activated by Cholecystokinin in Rat Pancreas both in Vitro and in Vivo
| Autor: | John A. Williams, Terrence Grady, Craig D. Logsdon, Andrzej Dabrowski |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Male
medicine.medical_specialty Indoles Vasoactive intestinal peptide Stimulation Biology digestive system Biochemistry Sincalide Rats Sprague-Dawley chemistry.chemical_compound Internal medicine medicine Animals Enzyme Inhibitors Protein kinase A Pancreas Molecular Biology Anisomycin Protein kinase C Cholecystokinin Cell-Free System Kinase JNK Mitogen-Activated Protein Kinases Bombesin Cell Biology Rats Enzyme Activation Kinetics Endocrinology chemistry Calcium-Calmodulin-Dependent Protein Kinases Tetradecanoylphorbol Acetate Carbachol Mitogen-Activated Protein Kinases Ceruletide Vasoactive Intestinal Peptide |
| Zdroj: | Journal of Biological Chemistry. 271:5686-5690 |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.271.10.5686 |
| Popis: | Stimulation of pancreatic acini from male Sprague-Dawley rats by both cholecystokinin (CCK)-8 and anisomycin caused an increase in p46jnk and p55jnk activities. Both forms of c-Jun amino-terminal kinase (JNK) were slightly activated at 5 min, reached a maximum at 30 min, and remained significantly increased at 60 min of CCK stimulation. By contrast, p42mapkwas activated fully by 5 min. In pancreatic acini stimulated with different concentrations of CCK for 30 min, the minimal and maximal JNK responses were observed at 30 pm and 100 nM CCK, respectively; p42mapk activation was, as previously reported, much more sensitive, with maximal activation by 1 nm CCK. Carbachol and bombesin also stimulated JNK activity, while vasoactive intestinal peptide did not. Neither activating protein kinase C nor increasing intracellular Ca2+ significantly activated JNK. In in vivo experiments, rats were infused intravenously for 5 and 15 min with a secretory (0.1 microg/kg/h) or supramaximal (10 microg/kg/h) dose of the CCK analog caerulein (CER). Secretory doses of CER induced a 4-fold increase of both forms of JNK in pancreatic tissue at 5 and 15 min, while at the same time points, supramaximal stimulation with CER caused 4- and 27-fold increases, respectively, of these kinase activities. The secretory dose of CER slightly increased the activities of both forms of mitogen-activated protein kinase, while the supramaximal dose induced a 10-fold increase of p42mapk at 5 min. In conclusion, JNKs and mitogen-activated protein kinases are rapidly activated in rat pancreatic acini stimulated with CCK as well as in pancreatic tissue during in vivo stimulation with CER. The large response to supramaximal CER stimulation may be of importance in the early pathogenesis of acute pancreatitis. |
| Databáze: | OpenAIRE |
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