Các khía cạnh điện hóa của cation trong tế bào lông của ốc tai chuột lang: một mô hình tế bào về sự di chuyển ion

Archives of oto-rhino-laryngology - Tập 247 - Trang 43-47 - 1990
K. Ikeda1, T. Morizono1
1Otophysiology Laboratory, Department of Otolaryngology, University of Minnesota Medical School, Minneapolis, USA

Tóm tắt

Điện thế dc và thành phần ion (K+, Na+ và Ca++) trong các tế bào lông của ốc tai đã được khảo sát bằng cách sử dụng điện cực vi chọn lọc ion. Nồng độ K+, Na+ và Ca++ lần lượt là 124.0 ± 29.8 mM, 6.9 ± 4.1 mM và 1.7 ± 1.4 μM trong các tế bào lông. Các độ chênh lệch điện thế điện hóa cho K+, Na+ và Ca++ qua màng đỉnh của các tế bào lông được tính toán lần lượt là 160.0 ± 29.8 mV, 87.6 ± 27.0 mV và 194.4 ± 35.2 mV. Những giá trị này cho K+, Na+ và Ca++ qua màng đáy bên của các tế bào lông là −12.6 ± 33.3 mV, 126.8 ± 28.3 mV và 170.8 ± 30.1 mV, tương ứng. Những phát hiện này đã được thảo luận trong bối cảnh của cơ chế vận chuyển cần thiết để duy trì thành phần ion của các tế bào lông.

Từ khóa

#tế bào lông #ốc tai #điện thế điện hóa #cation #cơ chế vận chuyển

Tài liệu tham khảo

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