{"id":"ce73ad31-a2a7-517b-a383-0ad1a27f5e52","stable_key":"911fb3c7-8cc3-5667-b677-5682fab67648:histidine-pht1-compartments","predicate":"supports","statement":"Five minutes after intravenous histidine, Pht1-null mouse brain parenchyma contained 28-48 percent less tracer-associated histidine than wild type, despite comparable plasma time courses and no corresponding CSF difference.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"dcc5b6da-deea-5b42-b6f3-b9683503a457","mechanism_event_label":"A normal circulating profile did not guarantee the same tissue exposure.","subject":{"id":"6ec79306-1983-566c-8dd0-b100a18afc9e","slug":"mouse-slc15a4","display_name":"Mouse peptide/histidine transporter Pht1 / Slc15a4","entity_type_key":"protein"},"object":{"id":"319a67a6-494c-56a4-945a-e9e07b46c685","slug":"mouse-brain-histidine-distribution","display_name":"Brain-parenchymal histidine after intravenous dosing","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"dcc5b6da-deea-5b42-b6f3-b9683503a457","stable_key":"911fb3c7-8cc3-5667-b677-5682fab67648:histidine-pht1-compartments-event","event_type":"observed_relationship","label":"A normal circulating profile did not guarantee the same tissue exposure.","description":"Five minutes after intravenous histidine, Pht1-null mouse brain parenchyma contained 28-48 percent less tracer-associated histidine than wild type, despite comparable plasma time courses and no corresponding CSF difference.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"6ec79306-1983-566c-8dd0-b100a18afc9e","slug":"mouse-slc15a4","display_name":"Mouse peptide/histidine transporter Pht1 / Slc15a4","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"319a67a6-494c-56a4-945a-e9e07b46c685","slug":"mouse-brain-histidine-distribution","display_name":"Brain-parenchymal histidine after intravenous dosing","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"44374451-3436-5136-a8ae-5dcc6d8c353b","slug":"histidine","display_name":"L-Histidine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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