{"id":"1876d476-2d42-5418-84f3-ca8e7c109af1","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-low-calcium-waves-tubules","predicate":"modulates","statement":"Low-K exposure increased calcium waves in ventricular and tubulated atrial cells, with a weaker response in untubulated atrial cells.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"b7ae3e94-55db-5d40-83ed-d83b7eca7101","mechanism_event_label":"Internal membrane architecture changed how low potassium disturbed calcium.","subject":{"id":"65e7fcad-670f-5dba-8488-896c86f2bbae","slug":"extracellular-potassium-concentration","display_name":"Extracellular potassium concentration","entity_type_key":"cellular_process"},"object":{"id":"8856b12a-1250-59e7-9581-97ec2a3bcca9","slug":"propagating-cardiac-calcium-waves","display_name":"Propagating cardiac calcium waves","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"b7ae3e94-55db-5d40-83ed-d83b7eca7101","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-low-calcium-waves-tubules-event","event_type":"biochemical_relationship","label":"Internal membrane architecture changed how low potassium disturbed calcium.","description":"Low-K exposure increased calcium waves in ventricular and tubulated atrial cells, with a weaker response in untubulated atrial cells.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"e359bc15-e675-5d83-b0fe-1d70814e130b","slug":"calcium-ion","display_name":"Calcium ion","entity_type_key":"ion"},"role":"measured signal","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"e3a8401d-1368-5851-879d-c5fa748650da","slug":"slc8a1","display_name":"Na+/Ca2+ exchanger 1 / SLC8A1","entity_type_key":"protein"},"role":"exchange pathway","stoichiometry":null,"state_label":"","sequence_order":1,"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":2,"notes":""},{"entity":{"id":"8856b12a-1250-59e7-9581-97ec2a3bcca9","slug":"propagating-cardiac-calcium-waves","display_name":"Propagating cardiac calcium waves","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"The calcium response to potassium depends on cellular transport organization.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Rat myocytes, 5.0 to 2.7 mM K, 3 minutes.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Architecture-dependent findings should not be generalized to all heart cells.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Potassium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"potassium","display_name":"Potassium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Rat","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Internal membrane architecture changed how low potassium disturbed calcium.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[tazmini-2020-cardiac] Hypokalemia Promotes Arrhythmia by Distinct Mechanisms in Atrial and Ventricular Myocytes (2020). https://pmc.ncbi.nlm.nih.gov/articles/PMC7098435/ DOI: 10.1161/CIRCRESAHA.119.315641","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Atrial/ventricular myocardium","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; 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Study references: [tazmini-2020-cardiac] Hypokalemia Promotes Arrhythmia by Distinct Mechanisms in Atrial and Ventricular Myocytes (2020). https://pmc.ncbi.nlm.nih.gov/articles/PMC7098435/ DOI: 10.1161/CIRCRESAHA.119.315641","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}