{"id":"ec74e454-f729-5db8-8d8e-4b855513eebf","stable_key":"195e8b84-ca5a-591a-a045-c55c53c8a01c:sodium-glt1-reversal","predicate":"under_test_gradients_reverses","statement":"Increasing extracellular potassium around cells loaded with sodium and glutamate evoked an outward, blocker-sensitive reversed transport current.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"c4c445ba-c2b8-5616-8468-6daf74e83009","mechanism_event_label":"Changing the ion gradients can reverse a transporter that normally clears glutamate.","subject":{"id":"5dd31e52-f51e-51f3-880e-240abcc0ab1d","slug":"potassium-ion","display_name":"Potassium ion","entity_type_key":"ion"},"object":{"id":"d5db2ae4-4777-5571-b33e-6f2fe3e16939","slug":"glt1-reversed-transport","display_name":"GLT-1-mediated reversed glutamate transport","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"c4c445ba-c2b8-5616-8468-6daf74e83009","stable_key":"195e8b84-ca5a-591a-a045-c55c53c8a01c:sodium-glt1-reversal-event","event_type":"biochemical_relationship","label":"Changing the ion gradients can reverse a transporter that normally clears glutamate.","description":"Increasing extracellular potassium around cells loaded with sodium and glutamate evoked an outward, blocker-sensitive reversed transport current.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"82bf19d7-94c6-56ad-9907-4b9e9139dcf7","slug":"glt1-assay-protein","display_name":"Mammalian glial glutamate transporter GLT-1 in the CHO assay","entity_type_key":"protein"},"role":"transporter","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":"intracellular_assay_ion","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"7da684a4-2641-5bc6-93ae-8c6aa384e487","slug":"glutamate","display_name":"L-Glutamate","entity_type_key":"small_molecule"},"role":"transported_substrate","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"5dd31e52-f51e-51f3-880e-240abcc0ab1d","slug":"potassium-ion","display_name":"Potassium ion","entity_type_key":"ion"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"d5db2ae4-4777-5571-b33e-6f2fe3e16939","slug":"glt1-reversed-transport","display_name":"GLT-1-mediated reversed glutamate transport","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/sodium-research/9822723.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"7612750fb1528dcd6212222b248bc74a2ec7a3813f50cbe5cf8ccdadbe448064\", \"start_char\": 0, \"end_char\": 1740, \"text_sha256\": \"7612750fb1528dcd6212222b248bc74a2ec7a3813f50cbe5cf8ccdadbe448064\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Whole-cell current reversal measurements","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Ion substitution, intracellular sodium/glutamate and extracellular potassium","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Stoichiometry inferred from reversal potentials; the predicted ischemic extracellular glutamate concentration is not an in-vivo result.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Sodium research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"sodium","display_name":"Sodium","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Mammalian GLT-1 expressed in Chinese hamster ovary cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Changing the ion gradients can reverse a transporter that normally clears glutamate.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[sodium-p9822723] Stoichiometry of the glial glutamate transporter GLT-1 expressed inducibly in a Chinese hamster ovary cell line selected for low endogenous Na+-dependent glutamate uptake. (1998). https://pubmed.ncbi.nlm.nih.gov/9822723/ DOI: 10.1523/jneurosci.18-23-09620.1998","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Plasma membrane","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"3d68821c-09aa-5a77-b63a-5f4779dfff42","evidence_kind":"source_excerpt","locator":"Lines 382-393","start_line":382,"end_line":393,"excerpt":"### sodium-glt1-reversal\nIncreasing extracellular potassium around cells loaded with sodium and glutamate evoked an outward, blocker-sensitive reversed transport current.\nCondition category: normal\nnutrient_topic: Sodium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Changing the ion gradients can reverse a transporter that normally clears glutamate.\norganism: Mammalian GLT-1 expressed in Chinese hamster ovary cells\ntissue_or_cell_type: Plasma membrane\nexperimental_model: Whole-cell current reversal measurements\nlimitations: Stoichiometry inferred from reversal potentials; the predicted ischemic extracellular glutamate concentration is not an in-vivo result.\nexposure: Ion substitution, intracellular sodium/glutamate and extracellular potassium\nevidence_span: {\"source_cache\": \"artifacts/sodium-research/9822723.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"7612750fb1528dcd6212222b248bc74a2ec7a3813f50cbe5cf8ccdadbe448064\", \"start_char\": 0, \"end_char\": 1740, \"text_sha256\": \"7612750fb1528dcd6212222b248bc74a2ec7a3813f50cbe5cf8ccdadbe448064\"}\n[sodium-p9822723] Stoichiometry of the glial glutamate transporter GLT-1 expressed inducibly in a Chinese hamster ovary cell line selected for low endogenous Na+-dependent glutamate uptake. 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