https://science.sciencemag.org/content/sci/150/3699/971.full.pdf

Pain mechanisms: a new theory.

Impulses and Physiological States in Theoretical Models of Nerve Membrane

Pain mechanisms: A new theory

Identification of a novel force-generating protein, kinesin, involved in microtubule-based motility

https://www.cell.com/cell/pdf/S0092-8674(03)00111-9.pdf

The Molecular Motor Toolbox for Intracellular Transport

Mechanical responses of the amphibian nerve-skin preparation to adrenergic stimulation were investigated by recording pressure changes at the skin surface with a piezo-electric sensor. When a dilute epinephrine (or norepinephrine) solution was applied to the inner skin surface, repetitive mechanical responses, representing quick swelling of the skin repeating at more or less regular intervals of about 1 min, were frequently observed. In about 10% of the preparations, the skin was found to undergo repetitive quick shrinkage (instead of swelling) under practically indistinguishable experimental conditions. Rapid volume changes occurring in the cytoplasmic gel of the gland cells are considered to be at the base of these repetitive mechanical responses.

Repetitive Mechanical Responses of the Amphibian Skin to Adrenergic Stimulation

The process of action potential production is analyzed in relation to the problem of energy transduction in the nerve. Describing the conditions required for the maintenance of excitability, the indispensability of divalent cations and the dispensability of univalent cations in the external medium are emphasized. Univalent cations with a strong tendency toward hydration enhance the action potential amplitude when added to the external Ca-salt solution. Experimental facts are described in consonance with the macromolecular interpretation of nerve excitation which postulates a transition of the negatively charged membrane macromolecules from a hydrophobic (resting) state to a hydrophilic (excited) state. Thermodynamic implications are discussed in relation to changes in enthalpy and volume accompanied by action potential production. Difficulties associated with analyses of excitation processes on a molecular basis are stressed.

Bioenergetics of Nerve Excitation

1.

The structure of the axolemma of the squid giant axon was studied by freeze-fracture electron microscopy.




2.

Three types of preparations were examined: intact axons, axons with their Schwann cell sheaths stripped off prior to freezing, and axons with their Schwann cell sheaths chemically detached but not mechanically removed.




3.

Because of a problem of cross-fracturing, the first two types of preparations revealed very few membrane faces of the axolemma. This cross-fracturing problem, however, was eliminated when we used a complementary replication method to fracture the third type of preparation.




4.

We found that the E-face of the axon membrane was smooth relative to the P-face, which showed many prominent intramembrane particles (IMP). The diameters of the typical IMP range from 6 to 15 nm.




5.

The P-face of the adjacent Schwann cells also showed many large IMP. The sizes and heights of the Schwann-cell IMP, however, appear to be more homogeneous than the P-face axolemma.




6.

On the basis of existing physiological and biochemical information about the estimated size and density of the so-called sodium-channel proteins, we suspect that some of the IMP at the P-face of the axolemma, especially those with diameters between 9 and 11 nm, may be associated with the intramembrane component of the sodium channels.

Ultrastructure of the Squid Axon Membrane as Revealed by Freeze-Fracture Electron Microscopy

The design and properties of thermal detectors constructed with multiple layers of polyvinylidene fluoride film are described. By use of these detectors, production of heat by the photoreceptors in the darkadapted bullfrog retina in response to brief pulses of very weak light was examined. In response to brief light pulses delivering an average of 1 photon per retinal rod, the retina was found to produce heat more-or-less abruptly after a latent period of 0.2 to 0.4s. At this level of pulse intensity, the thermal energy produced by the retina was approximately 1, 500, 000 times as large as the total radiant energy delivered to the retina for stimulation. It appears possible that a large number of disks in the rod outer segment are activated by absorption of a single photon.

Ichiji Tasaki

Papers

Repetitive Mechanical Responses of the Amphibian Skin to Adrenergic Stimulation

Bioenergetics of Nerve Excitation

Ultrastructure of the Squid Axon Membrane as Revealed by Freeze-Fracture Electron Microscopy

Detection of thermal responses of the retina by use of polyvinylidene fluoride multilayer detector.

A note on the local current associated with the rising phase of a propagating impulse in nonmyelinated nerve fibers