{"id":"50ae4226-1b09-50d7-a37f-d949c7185962","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-low-cardiac-pump-current","predicate":"supports","statement":"Lowering bath K from 5.0 to 2.7 mM reduced ventricular pump current and increased intracellular sodium.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"80cb2706-af9f-59ff-882d-16d166dc596a","mechanism_event_label":"With less extracellular potassium, sodium extrusion slowed.","subject":{"id":"65e7fcad-670f-5dba-8488-896c86f2bbae","slug":"extracellular-potassium-concentration","display_name":"Extracellular potassium concentration","entity_type_key":"cellular_process"},"object":{"id":"27c3e7bd-c6e1-5344-8130-b231a9da2cfb","slug":"sodium-potassium-atpase","display_name":"Sodium-potassium ATPase complexes","entity_type_key":"protein_family"},"evidence_count":1,"mechanism_event":{"id":"80cb2706-af9f-59ff-882d-16d166dc596a","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-low-cardiac-pump-current-event","event_type":"biochemical_relationship","label":"With less extracellular potassium, sodium extrusion slowed.","description":"Lowering bath K from 5.0 to 2.7 mM reduced ventricular pump current and increased intracellular sodium.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"485ac339-561d-5cd3-b569-5d3b67341a1e","slug":"atp1a2","display_name":"Sodium-potassium ATPase alpha-2 subunit / ATP1A2","entity_type_key":"protein"},"role":"implicated pump isoform","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"38de8704-84db-5770-ac1d-242cd787e798","slug":"sodium-ion","display_name":"Sodium ion","entity_type_key":"ion"},"role":"accumulating ion","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"c483148e-ce5a-5be0-a019-8217bfdd65d6","slug":"ouabain","display_name":"Ouabain","entity_type_key":"small_molecule"},"role":"isoform probe","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"65e7fcad-670f-5dba-8488-896c86f2bbae","slug":"extracellular-potassium-concentration","display_name":"Extracellular potassium concentration","entity_type_key":"cellular_process"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"27c3e7bd-c6e1-5344-8130-b231a9da2cfb","slug":"sodium-potassium-atpase","display_name":"Sodium-potassium ATPase complexes","entity_type_key":"protein_family"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; 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Study references: [aronsen-2015-cardiac] Hypokalaemia induces Ca2+ overload and Ca2+ waves in ventricular myocytes by reducing Na+,K+-ATPase alpha2 activity (2015). https://pmc.ncbi.nlm.nih.gov/articles/PMC4376427/ DOI: 10.1113/jphysiol.2014.279893","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"241226ee-6b7d-5cc7-9781-e6beb8ee1982","stable_key":"import-5102beb6-9f61-500e-af10-9ac63649e0b7","title":"Potassium: cross-nutrient mechanisms and deficiency (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"a8f89f8d84b48c0f93048dfc45f7f57a67dd9a7249968a096a14aeb03d8b7a52","revision_id":"de4ec6f4-58a1-537b-8169-97b783898df1","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}