Dataset Information

Contributions of degradation and brain-to-blood elimination across the blood-brain barrier to cerebral clearance of human amyloid-? peptide(1-40) in mouse brain.

ABSTRACT: The purpose of the present study was to estimate the relative contributions of degradation and brain-to-blood elimination processes to the clearance of microinjected human amyloid-? peptide(1-40) (hA?(1-40)) from mouse cerebral cortex, using a solid-phase extraction method together with a newly developed ultraperformance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) quantitation method for intact hA?(1-40). The clearance rate constant of hA?(1-40) in mouse cerebral cortex was determined to be 3.21 × 10(-2)/min under conditions where the saturable brain-to-blood elimination process across the blood-brain barrier (BBB) was expected to be saturated. Thus, this clearance rate constant should mainly reflect degradation. The [(125)I]hA?(1-40) elimination rate across the BBB under nonsaturating conditions was determined to be 1.48 × 10(-2)/min. Inhibition studies suggested that processes sensitive to insulin and phosphoramidon, which inhibit neprilysin, insulin-degrading enzyme, and endothelin-converting enzyme, are involved not only in degradation, but also in elimination of hA?(1-40). In conclusion, our results suggest a dominant contribution of degradation to cerebral hA?(1-40) clearance, and also indicate that a sequential process of degradation and elimination of degradation products is involved in cerebral hA?(1-40) clearance.

SUBMITTER: Ito S

PROVIDER: S-EPMC3824175 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Contributions of degradation and brain-to-blood elimination across the blood-brain barrier to cerebral clearance of human amyloid-β peptide(1-40) in mouse brain.

Ito Shingo S Matsumiya Kohta K Ohtsuki Sumio S Kamiie Junichi J Terasaki Tetsuya T

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20130821 11

The purpose of the present study was to estimate the relative contributions of degradation and brain-to-blood elimination processes to the clearance of microinjected human amyloid-β peptide(1-40) (hAβ(1-40)) from mouse cerebral cortex, using a solid-phase extraction method together with a newly developed ultraperformance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) quantitation method for intact hAβ(1-40). The clearance rate constant of hAβ(1-40) in mouse cerebral cortex was deter ...[more]

PMID: 23963369

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Dataset Information

Contributions of degradation and brain-to-blood elimination across the blood-brain barrier to cerebral clearance of human amyloid-? peptide(1-40) in mouse brain.

Publications

Contributions of degradation and brain-to-blood elimination across the blood-brain barrier to cerebral clearance of human amyloid-β peptide(1-40) in mouse brain.

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