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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Major current for depolarization in Purkinje fiber is of:
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The correct answer is  Purkinje fiber is a fast-response type or rapidly depolarizing fiber. The rapid depolarization is due a rapid influx of Na+ through the fast Na+ channels. Major current for depolarization in pacemaker cells is due to Ca++