Further studies of dopamine metabolism and function in Tetrahymena.
The large amounts of dopamine accumulated by cells of Tetrahymena pyriformis strain NT-1 and secreted into their growth medium were found to depend primarily upon an extracellular, non-enzymatic conversion of tyrosine to L-dihydroxyphenylalanine (L-DOPA); L-DOPA was then rapidly taken into the cells and transformed into dopamine enzymatically. Efforts to find physiologically significant dopamine binding sites on the cell surface or dopamine-sensitive adenylate cyclase activity were unsuccessful, suggesting that the catecholamine does not function in Tetrahymena as it does in higher animals.
D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D002455:Cell Division; D003470:Culture Media; D004298:Dopamine / Q000096:biosynthesis / Q000494:pharmacology / Q000502:physiology*; D007980:Levodopa / Q000378:metabolism; D009068:Movement / Q000187:drug effects; D011954:Receptors, Dopamine / Q000032:analysis; D013769:Tetrahymena pyriformis / Q000032:analysis / Q000378:metabolism* / Q000502:physiology; D014439:Tyramine / Q000378:metabolism
D003470:Culture Media; D011954:Receptors, Dopamine; D007980:Levodopa; D000262:Adenylyl Cyclases; D004298:Dopamine; D014439:Tyramine