Component
Human brain influx of carbon-11 ACHC tracer
Context-specific entity; species, compartment and exposure are stated on each claim.
1 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
What acts on it
After 100 mg/kg oral phenylalanine in six healthy men, plasma phenylalanine rose about elevenfold and brain uptake of the artificial large-neutral-amino-acid tracer carbon-11 ACHC fell from 0.036 to 0.019 mL/g/min.
Experimental context and source evidence
- availability_state
- biomarker_context Imported condition classification; unverified.
- evidence_access
- Primary abstract
- experimental_model
- Human PET loading study in six men.
- limitations
- ACHC is a transport tracer; each individual natural amino acid was not directly measured. This is not a normal-meal threshold.
- nutrient_topic
- L-Phenylalanine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Phenylalanine
- plain_language
- A large phenylalanine load can compete with other molecules for brain entry.
- primary_references
- Inhibition of neutral amino acid transport across the human blood-brain barrier by phenylalanine. · 1995 · https://pubmed.ncbi.nlm.nih.gov/7861158/ · DOI 10.1046/j.1471-4159.1995.64031252.x
- trigger_kind
- biomarker_context Imported condition classification; unverified.
L-Phenylalanine: transport, protein synthesis, cofactor recycling and cross-nutrient mechanisms (2026-09-19) · lines 190–196
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human PET loading study in six men. · source_derived_draft · unverified_draft
## l-phenylalanine-brain-competition A large phenylalanine load can compete with other molecules for brain entry. After 100 mg/kg oral phenylalanine in six healthy men, plasma phenylalanine rose about elevenfold and brain uptake of the artificial large-neutral-amino-acid tracer carbon-11 ACHC fell from 0.036 to 0.019 mL/g/min. Model: Human PET loading study in six men. Limitations: ACHC is a transport tracer; each individual natural amino acid was not directly measured. This is not a normal-meal threshold. Evidence access: Primary abstract Inhibition of neutral amino acid transport across the human blood-brain barrier by phenylalanine. · 1995 · https://pubmed.ncbi.nlm.nih.gov/7861158/ · DOI 10.1046/j.1471-4159.1995.64031252.x
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.