title: Roles of tyrosine kinase in insulin action on cell volume of fetal rat type II pneumocyte.
abstract: The aim of the present study was to investigate the roles of tyrosine kinase (TK) in the insulin action on cell volume in fetal rat (20-day gestational age) type II pneumocyte. Insulin (100 nmol/l) increased cell volume, and this insulin (100 nmol/l) action was completely blocked by 50 micromol/l bumetanide (BMT) and 10 micromol/l amiloride (AML). This observation indicates that 100 nmol/l insulin activates BMT-sensitive Na+/K+/2Cl- cotransporter and AML-sensitive pathways. The stimulatory action of 100 nmol/l insulin on BMT-sensitive Na+/K+/2Cl- cotransporter was completely abolished by 10 micromol/l lavendustin A (LAV-A, an inhibitor of TK), however 100 nmol/l insulin could stimulate AML-sensitive pathways even in LAV-A (10 micromol/l)-treated cells. These observations indicate that the insulin (100 nmol/l) action on the BMT-sensitive Na+/K+/2Cl- cotransporter is mediated through TK-dependent pathways, while 100 nmol/l insulin requires a TK-independent pathway to show the stimulatory action on the AML-sensitive pathways. From these observations we conclude that TK-dependent and -independent pathways are involved in the insulin (100 nmol/l) signaling in fetal rat type II pneumocyte.
authors.affiliation: MRC Group in Lung Development, Hospital for Sick Children Research Institute, University of Toronto, Faculty of Medicine, Toronto, Ontario, Canada M5G 1X8.
authors.forename: Y
authors.initials: Y
authors.lastname: Marunaka
authors.forename: Y
authors.initials: Y
authors.lastname: Shintani
authors.forename: E
authors.initials: E
authors.lastname: Sugimoto
authors.forename: N
authors.initials: N
authors.lastname: Niisato
mesh_terms: D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D002034:Bumetanide / Q000494:pharmacology; D002352:Carrier Proteins / Q000378:metabolism; D048429:Cell Size / Q000187:drug effects*; D002478:Cells, Cultured; D004232:Diuretics / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000494:pharmacology*; D008168:Lung / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D010636:Phenols / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D015222:Sodium Channels / Q000187:drug effects / Q000378:metabolism; D028021:Sodium-Potassium-Chloride Symporters
chemical_list: D002352:Carrier Proteins; D004232:Diuretics; D004791:Enzyme Inhibitors; D007004:Hypoglycemic Agents; D007328:Insulin; D010636:Phenols; D015222:Sodium Channels; D028021:Sodium-Potassium-Chloride Symporters; D002034:Bumetanide; C062898:lavendustin A; D000584:Amiloride; D011505:Protein-Tyrosine Kinases