{"id":"97feaef2-c2b0-5379-81ad-21badc95dfe1","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-depletion-aqp2-abundance","predicate":"depletion-decreases","statement":"Eleven days of potassium deprivation reduced AQP2 abundance in rat cortical and medullary collecting ducts.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"d8d19b28-4b93-550c-9fe8-2687e61cf00b","mechanism_event_label":"Less water-channel protein accompanied the concentrating defect.","subject":{"id":"87435e1d-e1cd-57da-984b-203b2f5f29a4","slug":"potassium","display_name":"Potassium","entity_type_key":"nutrient_element"},"object":{"id":"0cf1432e-2f5f-542c-8980-6894da46cce6","slug":"aqp2","display_name":"Aquaporin-2 / AQP2","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"d8d19b28-4b93-550c-9fe8-2687e61cf00b","stable_key":"5102beb6-9f61-500e-af10-9ac63649e0b7:k-depletion-aqp2-abundance-event","event_type":"biochemical_relationship","label":"Less water-channel protein accompanied the concentrating defect.","description":"Eleven days of potassium deprivation reduced AQP2 abundance in rat cortical and medullary collecting ducts.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"87435e1d-e1cd-57da-984b-203b2f5f29a4","slug":"potassium","display_name":"Potassium","entity_type_key":"nutrient_element"},"role":"upstream","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"0cf1432e-2f5f-542c-8980-6894da46cce6","slug":"aqp2","display_name":"Aquaporin-2 / AQP2","entity_type_key":"protein"},"role":"downstream","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"d31225b7-8e94-5857-9ea1-67ac794b1f15","slug":"water","display_name":"H2O","entity_type_key":"small_molecule"},"role":"transported-molecule","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"endpoint","value_text":"Eleven days of potassium deprivation reduced AQP2 abundance in rat cortical and medullary collecting ducts.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental-exposure","value_text":"Rats with 11 days of potassium deprivation; AQP2 immunoblot/immunocytochemistry, urine volume, and potassium refeeding.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Rats with 11 days of potassium deprivation; AQP2 immunoblot/immunocytochemistry, urine volume, and potassium refeeding.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Parallel changes and refeeding support reversibility, but no AQP2-specific rescue isolated its complete contribution.","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":"Rattus norvegicus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Less water-channel protein accompanied the concentrating defect.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[marples-1996-aqp2] Hypokalemia-induced downregulation of aquaporin-2 water channel expression in rat kidney medulla and cortex (1996). https://pubmed.ncbi.nlm.nih.gov/8621781/ DOI: 10.1172/JCI118628","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"cortical and inner medullary collecting ducts","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"cc889e97-6a6b-5bbd-a234-6c488c0222e8","evidence_kind":"source_excerpt","locator":"Lines 1386-1397","start_line":1386,"end_line":1397,"excerpt":"### k-depletion-aqp2-abundance\nEleven days of potassium deprivation reduced AQP2 abundance in rat cortical and medullary collecting ducts.\nCondition category: nutrient_deficiency\nnutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Less water-channel protein accompanied the concentrating defect.\norganism: Rattus norvegicus\ntissue_or_cell_type: cortical and inner medullary collecting ducts\nexperimental_model: Rats with 11 days of potassium deprivation; AQP2 immunoblot/immunocytochemistry, urine volume, and potassium refeeding.\nlimitations: Parallel changes and refeeding support reversibility, but no AQP2-specific rescue isolated its complete contribution.\nexperimental-exposure: Rats with 11 days of potassium deprivation; AQP2 immunoblot/immunocytochemistry, urine volume, and potassium refeeding.\nendpoint: Eleven days of potassium deprivation reduced AQP2 abundance in rat cortical and medullary collecting ducts.\n[marples-1996-aqp2] Hypokalemia-induced downregulation of aquaporin-2 water channel expression in rat kidney medulla and cortex (1996). https://pubmed.ncbi.nlm.nih.gov/8621781/ DOI: 10.1172/JCI118628","model_system":"Rats with 11 days of potassium deprivation; AQP2 immunoblot/immunocytochemistry, urine volume, and potassium refeeding.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [marples-1996-aqp2] Hypokalemia-induced downregulation of aquaporin-2 water channel expression in rat kidney medulla and cortex (1996). https://pubmed.ncbi.nlm.nih.gov/8621781/ DOI: 10.1172/JCI118628","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}