title: Local anaesthetics including benzyl alcohol activate the adenylate cyclase in Trypanosoma brucei by a calcium-dependent mechanism.
abstract: 1. The adenylate cyclase of Trypanosoma brucei is activated by local anaesthetics. 2. Activation of adenylate cyclase by the local anaesthetic, benzyl alcohol, requires Ca2+. 3. The kinetics of the presteady state reveal that the activation step occurs prior to and is separate from the catalytic step. 4. The activation step in the presence of Ca2+ can be stimulated some 200-fold and is highly co-operative with respect to benzyl alcohol concentration. 5. The mechanism by which local anaesthetics activate may be by exposing the Ca2+ -binding site of the Ca2+ receptor which is oriented towards the hydrophobic regions of the plasma membrane in the basal state.
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism*; D000779:Anesthetics, Local / Q000494:pharmacology*; D019905:Benzyl Alcohol; D001592:Benzyl Alcohols / Q000494:pharmacology*; D001593:Benzyl Compounds / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology*; D000242:Cyclic AMP / Q000096:biosynthesis; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D014346:Trypanosoma brucei brucei / Q000201:enzymology*
chemical_list: D000779:Anesthetics, Local; D001592:Benzyl Alcohols; D001593:Benzyl Compounds; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D019905:Benzyl Alcohol; D002118:Calcium