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Ascorbate itself does not cross the membrane, which is precisely why a shuttle is required.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Cold water immersion research collection; topical membership is not evidence of a direct clinical effect, and a therapeutic exposure is not a dietary intake.","comparator":null,"unit":null,"notes":"","entity":{"slug":"cold-water-immersion","display_name":"Cold water immersion","entity_type_key":"drug"}},{"dimension":"organism","value_text":"Bovine","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The vitamin cannot cross into the vesicle, so the cell passes electrons across the membrane instead.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[cold-p3949732] Evidence for an ascorbate shuttle for the transfer of reducing equivalents across chromaffin granule membranes. 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Ascorbate itself does not cross the membrane, which is precisely why a shuttle is required.\nexposure: Tyramine- or dopamine-stimulated turnover with extragranular ascorbate\nevidence_span: {\"source_cache\": \"artifacts/cold-research/3949732.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"9db1233389aeb375adfd655ea04f39ccb05e22773f367aaa1292bb21698242e1\", \"start_char\": 0, \"end_char\": 2000, \"text_sha256\": \"9db1233389aeb375adfd655ea04f39ccb05e22773f367aaa1292bb21698242e1\"}\n[cold-p3949732] Evidence for an ascorbate shuttle for the transfer of reducing equivalents across chromaffin granule membranes. 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