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F Conti

Publications and source records attributed to F Conti.

At least 271 records · Page 15Linked to original sources
PubMed1970

Changes in extrinsic fluorescence in squid axons during voltage-clamp.

Fluorescence changes in squid axons were examined after staining with rhodamine B, pyronin B, or 8-anilinonaphthalene-1-sulfonate by intracellular application. Gradual changes in fluorescence were detected during both hyperpolarizing and depolarizing voltage-clamp pulses. Abrupt changes were often observed at the onset and at the end of voltage-clamp. Possible sources of artifact in optical measurements of this type and some implications of the findings are discussed.

Animals↗
PubMed1970

Subthreshold behavior and phenomenological impedance of the squid giant axon.

The oscillatory behavior of the cephalopod giant axons in response to an applied current has been established by previous investigators. In the study reported here the relationship between the familiar "RC" electrotonic response and the oscillatory behavior is examined experimentally and shown to be dependent on the membrane potential. Computations based on the three-current system which was inferred from electrical measurements by Hodgkin and Huxley yield subthreshold responses in good agreement with experimental data. The point which is developed explicitly is that since the three currents, in general, have nonzero resting values and two currents, the "Na" system and the "K" system, are controlled by voltage-dependent time-variant conductances, the subthreshold behavior of the squid axon in the small-signal range can be looked upon as arising from phenomenological inductance or capacitance. The total phenomenological impedance as a function of membrane potential is derived by linearizing the empirically fitted equations which describe the time-variant conductances. At the resting potential the impedance consists of three structures in parallel, namely, two series RL elements and one series RC element. The true membrane capacitance acts in parallel with the phenomenological elements, to give a total impedance which is, in effect, a parallel R, L, C system with a "natural frequency" of oscillation. At relatively hyperpolarized levels the impedance "degenerates" to an RC system.

Animals↗