شبيه‌سازي الگوهاي شليک پتانسيل عمل نورون‌هاي هرمي و کنترل مشخصه‌هاي آنها با استفاده از جريان‌هاي پتاسيمي گذرا
محورهای موضوعی : مهندسی برق و کامپیوترزهرا دانش‌پرور 1 , محمدرضا دلیری 2 *
1 - دانشگاه علم و صنعت ايران
2 - دانشگاه علم و صنعت ايران
کلید واژه: پاسخ نورونی مدل‌سازی سلولی هسته حلزونی پشتی (DCN) تأخیر پاسخ,
چکیده مقاله :
سلول‌هاي هرمي هسته حلزوني پشتي (DCN)، داراي الگوهاي پاسخ نوروني با تأخيرهاي متفاوتي هستند. اين سلول‌ها داراي دو جريان پتاسيمي گذرا به نام‌هاي IKif و IKis هستند که به‌ترتيب داراي دريچه‌هاي نافعال شوندگي با ديناميک سريع و آهسته مي‌باشند. جريان هاي پتاسيمي گذرا يعني جريان‌هاي داراي دريچه‌هاي فعال‌شوندگي و نافعال‌شوندگي در تنظيم تأخير قبل از شليک پتانسيل‌هاي عمل تأثير دارند. اين جريان‌ها الگوهاي متفاوتي از پاسخ نوروني مانند شليک پيوسته بلافاصله بعد از اعمال تحريک يا پاسخ‌گويي با تأخيري طولاني بعد از ايجاد يک تک اسپايک پيشتاز يا حتي بدون تک اسپايک آغازين را به نمايش مي‌گذارند. در گزارش پيش رو، رفتار پاسخ نوروني سلول‌هاي هرمي DCN با استفاده از يک مدل دارای رسانایی 3متغيره شبيه‌سازي شده است و در ادامه با استفاده از روش‌هاي تحليلي سيستمهاي ديناميکي، مکانيسم‌هاي زيربنايي پاسخ‌هاي نوروني مدل ارائه‌شده توجيه شده است. اين مدل نسخه کاهش‌يافته‌اي از یک مدل الکتروفیزیولوژیکی با 10 متغير حالت می‌باشد.
Pyramidal cells of the dorsal cochlear nucleus (DCN) represent firing types with different latencies. They incorporate two transient potassium currents namely Ikif and Ikis with fast and slow inactivation gatings, respectively. Transient potassium currents i.e. currents having both activation and inactivation gatings influence on the latency before firing. These currents cause different neural responses containing a regular firing, or a long latency before firing with or without a leading spike. In this paper, the firing behavior of DCN pyramidal cells is simulated first with a 3-variable conductance-based model. Next, mechanisms underlie neural responses of the model are analyzed by dynamical systems analysis methods. The model is a reduced version of Kanold and Manis model with 10 variables.
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