{"id":"40d90b10-64df-5e96-9852-b8fbadaeb334","stable_key":"ae1ed35d-8ce7-5936-9067-a641374bbf79:carnosine-rat-muscle-null","predicate":"knockout_did_not_reduce","statement":"Carns1 deletion did not impair measured skeletal-muscle force, fatigability, exercise capacity or buffering in the rats.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"a4107f26-d221-5b95-9261-51912b9cf894","mechanism_event_label":"The cardiac phenotype did not apply equally to skeletal muscle.","subject":{"id":"b15ba44e-53f3-50fe-8d64-ddf32f8c96c1","slug":"rat-carns1","display_name":"Rat carnosine synthase / Carns1","entity_type_key":"protein"},"object":{"id":"4ef52656-edd2-52db-923a-8b42bb788e2c","slug":"rat-muscle-buffering-contraction","display_name":"Rat skeletal-muscle buffering and contraction in Carns1 knockout","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"a4107f26-d221-5b95-9261-51912b9cf894","stable_key":"ae1ed35d-8ce7-5936-9067-a641374bbf79:carnosine-rat-muscle-null-event","event_type":"observed_relationship","label":"The cardiac phenotype did not apply equally to skeletal muscle.","description":"Carns1 deletion did not impair measured skeletal-muscle force, fatigability, exercise capacity or buffering in the rats.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"b15ba44e-53f3-50fe-8d64-ddf32f8c96c1","slug":"rat-carns1","display_name":"Rat carnosine synthase / Carns1","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"4ef52656-edd2-52db-923a-8b42bb788e2c","slug":"rat-muscle-buffering-contraction","display_name":"Rat skeletal-muscle buffering and contraction in Carns1 knockout","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"9998eb9b-0d09-58c9-885b-a442477dec8d","slug":"carnosine","display_name":"L-Carnosine / beta-alanyl-L-histidine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Same rat model.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Tissue difference rather than opposing statements about the same condition.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Carnosine collection; isomer, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"carnosine","display_name":"L-Carnosine / beta-alanyl-L-histidine","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"The cardiac phenotype did not apply equally to skeletal muscle.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Histidine dipeptides are key regulators of excitation-contraction coupling in cardiac muscle: Evidence from a novel CARNS1 knockout rat model. · 2021 · https://pubmed.ncbi.nlm.nih.gov/34038814/ · DOI 10.1016/j.redox.2021.102016","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"1facf1c8-4fa8-5a4d-bbfc-80a76aa826c1","evidence_kind":"source_excerpt","locator":"Lines 452-458","start_line":452,"end_line":458,"excerpt":"## carnosine-rat-muscle-null\nThe cardiac phenotype did not apply equally to skeletal muscle.\nCarns1 deletion did not impair measured skeletal-muscle force, fatigability, exercise capacity or buffering in the rats.\nModel: Same rat model.\nLimitations: Tissue difference rather than opposing statements about the same condition.\nEvidence access: Primary abstract\nHistidine dipeptides are key regulators of excitation-contraction coupling in cardiac muscle: Evidence from a novel CARNS1 knockout rat model. · 2021 · https://pubmed.ncbi.nlm.nih.gov/34038814/ · DOI 10.1016/j.redox.2021.102016","model_system":"Same rat model.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"87dc5af2-4eb6-5980-b7e0-bf3697b1156e","stable_key":"import-ae1ed35d-8ce7-5936-9067-a641374bbf79","title":"Carnosine: synthesis, transport, carbonyl chemistry and nutrient interactions (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"469cbc38203db56bd031f9d8a2dd2bfa387713950ca30199511cd137e927aa7a","revision_id":"cc409a15-8b04-50ee-a7ff-d1bf32f686bb","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}