Insulin sensitizes a cultured rat osteogenic sarcoma cell line to hormones which activate adenylate cyclase.
Pretreatment of the osteogenic sarcoma cell line UMR-106-01 with insulin results in sensitization to both parathyroid hormone (PTH) and isoproterenol. In insulin-pretreated cells, the two hormones cause a significantly greater cyclic AMP (cAMP) accumulation than in noninsulin-treated cells. In the presence of cholera toxin, which enhances cAMP production by these cells in both the basal and PTH-stimulated state, the effect of insulin is maintained. In the presence of pertussis toxin, which has no effect on basal cAMP accumulation but enhances both PTH and isoproterenol stimulation, insulin sensitization for both hormones is abolished. These data suggest that insulin sensitizes these cells to subsequent hormone stimulation by lessening the action of an inhibitory guanine nucleotide regulatory protein, possibly Gi.
Hickman
J
J
Department of Endocrinology, Royal North Shore Hospital, St. Leonards, Australia.
McElduff
A
A
D037361:Adenylate Cyclase Toxin; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D001859:Bone Neoplasms / Q000201:enzymology / Q000473:pathology* / Q000503:physiopathology; D002772:Cholera Toxin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000502:physiology; D007328:Insulin / Q000494:pharmacology*; D007545:Isoproterenol / Q000494:pharmacology*; D010281:Parathyroid Hormone / Q000494:pharmacology*; D037342:Pertussis Toxin; D051381:Rats; D012513:Sarcoma, Experimental / Q000201:enzymology / Q000473:pathology* / Q000503:physiopathology; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D037361:Adenylate Cyclase Toxin; D007328:Insulin; D010281:Parathyroid Hormone; D010566:Virulence Factors, Bordetella; D002772:Cholera Toxin; D000242:Cyclic AMP; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases; D007545:Isoproterenol