Histology USMLE Step 1 Practice Question
A 68-year-old man with hypertension (BP 165/95 mmHg, HR 108/min, RR 20/min) dies from acute myocardial infarction complications. Autopsy reveals elevated cardiac troponin I (8.2 ng/mL) and anterior wall infarction on gross examination. Histologic sections of viable myocardium away from the infarct border show branched fibers with centrally located nuclei and specialized cell-cell junctions that electrically couple adjacent cells. Coronary atherosclerosis is noted; valvular disease is absent. Which of the following structures is most responsible for that electrical coupling?
Answer choices
- ACostameres
- BHemidesmosomes
- CGap junctions within intercalated discsCorrect answer
- DTight junctions
- EDesmosomes only
- FAdherens junctions with N-cadherin
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