title: Conversion of p-tyrosine to p-tyramine in the isolated perfused rat kidney: modulation by perfusate concentrations of p-tyrosine.
abstract: We used the isolated perfused rat kidney to evaluate the role of renal decarboxylation of p-tyrosine as the source of urinary p-tyramine. Kidneys were perfused with concentrations of p-tyrosine ranging from 0.02 mM to 2.0 mM. p-Tyramine was measured by a sensitive and specific radioenzymatic assay. An increase in the perfusate concentration of p-tyrosine resulted in a significant increase in p-tyramine production that was blocked by the addition of NSD-1015, an inhibitor of aromatic-1-amino decarboxylase (AADC). We conclude p-tyrosine is the precursor for the renal production of p-tyramine, renal AADC catalyzes the formation of urinary p-tyramine, synthesized p-tyramine is predominantly excreted in the urine, and p-tyramine synthesis is modulated by the arterial delivery of p-tyrosine to the kidney.
authors.affiliation: Department of Medicine, University of Louisville, Kentucky 40292.
authors.forename: M E
authors.initials: ME
authors.lastname: Brier
authors.forename: R R
authors.initials: RR
authors.lastname: Bowsher
authors.forename: P R
authors.initials: PR
authors.lastname: Mayer
authors.forename: D P
authors.initials: DP
authors.lastname: Henry
mesh_terms: D000818:Animals; D007668:Kidney / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D014439:Tyramine / Q000378:metabolism* / Q000652:urine; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D014443:Tyrosine; D014439:Tyramine