Model investigation of firing mechanisms of mammalian neurons
Tóm tắt
A model of electrical activity of mammalian neurons, based on properties of the corresponding ionic components of the transmembrane current, is suggested. Its analysis showed that two types of firing are possible for these neurons. First, the firing pattern is determined by fast sodium and delayed potassium currents, and the period of oscillations is 74±27 msec. Second, the firing pattern is determined by calcium and Ca-activated potassium currents, and the mean duration of the interspike interval is 850±40 msec. A comprehensive examination of all ionic currents enabled two mechanisms of lengthening of the interspike interval (adaptation) of the discharge to be predicted. One is due to the fast potassium current, the other to accumulation of Ca++ ions inside the cell and the development of a Ca-activated potassium current.
Tài liệu tham khảo
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