{"id":"3b2af6a8-b2ff-5299-89c8-4b99bb7cb5f4","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-abs-anacidity-jejunum","predicate":"did-not-detectably-reduce","statement":"In the same crossover experiment, jejunal release of labeled liver cobalamins was near 90% after either omeprazole or placebo, despite earlier gastric effects.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"7e173e24-8f0e-5b69-8917-cd64da4c89ae","mechanism_event_label":"Most liver-bound B12 was still released by the jejunum.","subject":{"id":"a9941a82-a3e4-5b0a-9a98-484451d914e0","slug":"omeprazole","display_name":"Omeprazole","entity_type_key":"small_molecule"},"object":{"id":"f85f147c-2ad1-54e5-8036-c657ea6614b1","slug":"jejunal-food-cobalamin-release","display_name":"Jejunal release of food-bound cobalamin","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"7e173e24-8f0e-5b69-8917-cd64da4c89ae","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-abs-anacidity-jejunum-event","event_type":"observed_intervention","label":"Most liver-bound B12 was still released by the jejunum.","description":"In the same crossover experiment, jejunal release of labeled liver cobalamins was near 90% after either omeprazole or placebo, despite earlier gastric effects.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"b6d9b937-895d-5e0a-8cc5-0454a0b7d373","slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"},"role":"nutrient","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"a9941a82-a3e4-5b0a-9a98-484451d914e0","slug":"omeprazole","display_name":"Omeprazole","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"f85f147c-2ad1-54e5-8036-c657ea6614b1","slug":"jejunal-food-cobalamin-release","display_name":"Jejunal release of food-bound cobalamin","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Double-blind crossover in 14 healthy humans using 57Co-labeled rabbit liver","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Short-term omeprazole versus placebo","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Luminal release is not systemic absorption; this observation cannot exclude long-term effects on status.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Most liver-bound B12 was still released by the jejunum.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[kittang-1987-anacidity] Effect of gastric anacidity on the release of cobalamins from food and their subsequent binding to R-protein. (1987). https://pubmed.ncbi.nlm.nih.gov/3423731/ DOI: 10.3109/00365528708991952","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Upper jejunal lumen","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"6adea16a-e910-562f-85c9-5c6b2124eb75","evidence_kind":"source_excerpt","locator":"Lines 140-151","start_line":140,"end_line":151,"excerpt":"### b12-abs-anacidity-jejunum\nIn the same crossover experiment, jejunal release of labeled liver cobalamins was near 90% after either omeprazole or placebo, despite earlier gastric effects.\nCondition category: normal\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Most liver-bound B12 was still released by the jejunum.\norganism: Homo sapiens\ntissue_or_cell_type: Upper jejunal lumen\nexperimental_model: Double-blind crossover in 14 healthy humans using 57Co-labeled rabbit liver\nlimitations: Luminal release is not systemic absorption; this observation cannot exclude long-term effects on status.\nexposure: Short-term omeprazole versus placebo\ncross_nutrient: false\n[kittang-1987-anacidity] Effect of gastric anacidity on the release of cobalamins from food and their subsequent binding to R-protein. (1987). https://pubmed.ncbi.nlm.nih.gov/3423731/ DOI: 10.3109/00365528708991952","model_system":"Double-blind crossover in 14 healthy humans using 57Co-labeled rabbit liver","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [kittang-1987-anacidity] Effect of gastric anacidity on the release of cobalamins from food and their subsequent binding to R-protein. (1987). https://pubmed.ncbi.nlm.nih.gov/3423731/ DOI: 10.3109/00365528708991952","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"73145023-2982-5848-aff2-8d8875d6b9c5","stable_key":"import-7fc92b9e-9cbf-556e-8719-6b5244625250","title":"Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. 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