Premium
Angiotensinogen in Cerebrospinal Fluid Corresponds Chromatographically to the γ‐Form of Plasma Angiotensinogen
Author(s) -
Moffett R. Bruce
Publication year - 1987
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1987.tb00970.x
Subject(s) - prohormone , chemistry , cerebrospinal fluid , glycoprotein , peptide , endocrinology , sodium , amino acid , medicine , gel electrophoresis , biochemistry , hormone , biology , organic chemistry
Abstract: Angiotensinogen (Aogen) (CA 11002–13–14), the prohormone of the neuro‐ and vasoactive peptide angioten‐ sin II (Ang II) (CA 11128–99–7), is found in dog brain as well as in dog plasma. At 2–4 μg/ml CSF, Aogen comprises 1‐ 2% of the total protein in dog CSF. Immunopurified CSF and plasma Aogen were compared by sodium dodecyl sulfate polyacrylamide gel electrophoresis and anion‐exchange HFLC. Two major (α‐ and β‐) forms and one minor (γ‐) form of Aogen were observed in dog plasma. The majority of Aogen in dog CSF was Chromatographically identical to the γ‐form of plasma Aogen; α‐ and β‐Aogen forms comprised <5% of the total CSF Aogen. The N‐terminal amino acid sequences of α‐, β‐, and γ‐Aogen identified these proteins as members of the Aogen family. The N‐terminal amino acid sequence of CSF γ‐Aogen was Asp‐Arg‐Val‐Tyr‐Ile‐His‐Pro‐Phe‐His‐Leu‐Leu‐Val‐Tyr‐Ser‐Lys‐Ser‐ Ser‐(X)‐Glu‐. More basic than either a‐ or β‐Aogen, γ‐ Aogen was shown to be a glycoprotein with an apparent molecular weight (M r ) of 58,000. CSF [des Ang I]‐Aogen exhibited a greater anion‐exchange HPLC retention. CSF, however, contained only minor amounts of [des Ang I]‐ Aogen. These analyses have demonstrated that brain overwhelmingly releases one particular Aogen into the CSF; however, very little of this brain Aogen is utilized for the production of Ang I.