Enzymatic cleavage of pyroglutamyl-histidyl-dopamine, a TRH-related pseudo-peptide by porcine serum and brain hoimogenate.
The Pseudo-peptide (pGlu-His-Dopamine) was subjected to enzymatic degradation by porcine serum and brain homogenate. The digests were quantitatively analyzed by HPLC to provide evidence for liberation of pyroglutamic acid and dopamine in serum and of pyroglutamic acid in brain. The yield of liberation of pGlu is about 3% in serum digests and about 0.70% in brain digests after 3 minutes incubation. The time course of the yield of liberation of both pGlu and dopamine in serum digests is determined. The "stability in vitro" toward enzymes of serum and brain homogenate of a new type of drug based on the combination of peptidic fragment of TRH-(Thyrotropin-Releasing Hormone:pGlu-His-Pro-NH2) with a non peptide moiety (dopamine) is considered and discussed.
Richard
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C
Unité N 16 de l'INSERM, Place de Verdun, 59.045-Lille, France.
Boersma
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A
Han
K K
KK
Morier
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E
Rips
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R
D000818:Animals; D001923:Brain Chemistry; D004298:Dopamine / Q000031:analogs & derivatives / Q000097:blood; D010446:Peptide Fragments / Q000032:analysis; D011761:Pyrrolidonecarboxylic Acid / Q000097:blood / Q000737:chemistry; D013552:Swine; D013973:Thyrotropin-Releasing Hormone / Q000737:chemistry*; D014020:Tissue Extracts / Q000737:chemistry*
D010446:Peptide Fragments; D014020:Tissue Extracts; D013973:Thyrotropin-Releasing Hormone; D011761:Pyrrolidonecarboxylic Acid; D004298:Dopamine