Biomechanical Stresses Due to Tissue Micromotion at the Neural Interface Modulate Intracellular Membrane Potentials

Observations of the electrophysiological properties of cells are important for understanding cellular functions and their underlying mechanisms. Short action potentials in axons are essential to rapidly deliver signals from the neuronal cell body to the terminals, whereas longer action potentials are required for sufficient calcium influx for transmitter release at the synaptic terminals and for cardiomyocyte and smooth muscle contractions. To accurately observe the shape and timing of depolarizations, it is essential to measure changes in the intracellular membrane potential. The ability to record action potentials and intracellular membrane potentials from mammalian cells and neurons was made possible by Ling and Gerard’s discovery in 1949, when they introduced sharp glass electrode with a submicron sized tip. Because of the small tip size, the sharp glass electrode could penetrate the cell membrane with little damage, which was one of the major breakthroughs in cellular electrophysiology and is the basic principle of the intracellular recording technique to date, providing the basis for further innovation of patch-clamp electrophysiology. I report a proof-of-principle demonstration of a novel method for recording intracellular potentials without penetrating the cell membrane using glass electrodes. We discovered that magnetically held transmembrane conductive nanoparticles can function as an intracellular electrode to detect transmembrane membrane potentials similar to those obtained by the conventional patch-clamp recording method. NEW & NOTEWORTHY To accurately observe the shape of action potentials, it is essential to perform intracellular recordings. I present a method to record intracellular potentials using magnetically held magnetic conductive nanoparticles in the membrane as an electrode. These nanoparticles function similarly to a conventional intracellular microelectrode. This is the first report to apply conductive nanoparticles to detect action potentials in the form of electrical signals.

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THE CHANGES OF INTRACELLULAR MEMBRANE POTENTIALS IN CELLS OF THE SEMINIFEROUS TUBULES OF RATS AND INTRACELLULAR STAINING

The Japanese Journal of Urology ◽

10.5980/jpnjurol1928.73.9_1116 ◽

1982 ◽

Vol 73 (9) ◽

pp. 1116-1122

Author(s):

Masanori Yamamoto ◽

Koji Miyake ◽

Hideo Mitsuya ◽

Hirokazu Kitamura ◽

Kazuyori Yamada

Keyword(s):

Membrane Potentials ◽

Seminiferous Tubules ◽

Intracellular Membrane ◽

Intracellular Staining ◽

In Cells

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Active vascular smooth muscle tone and venous membrane potentials during hemorrhage

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1980.238.2.h144 ◽

1980 ◽

Vol 238 (2) ◽

pp. H144-H152

Author(s):

W. J. Stekiel ◽

W. J. Willems ◽

D. R. Harder ◽

J. H. Lombard

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Vascular Tone ◽

Muscle Tone ◽

Venous Pressure ◽

Membrane Potentials ◽

Intracellular Membrane ◽

Small Intestinal ◽

Vascular Smooth Muscle Tone

To clarify mechanisms leading to failure of compensatory vascular tone in splanchnic blood vessels during prolonged hypotensive stress, anesthetized rats were maintained at a constant mean arterial pressure of 35 mmHg by hemorrhage into an external reservoir until 40% autoinfusion of maximum bled volume. In vivo intracellular membrane potentials (Em) of small intestinal mesenteric veins (300--500 micrometers) were measured before and during the compensatory (bleedout) and decompensatory (autinfusion) phases of the hypotensive period to assess the state of vascular smooth muscle (VSM) excitation. During the compensatory phase, Em decreased from -41 +/- 1 mV (prehemorrhage) to -31 +/- 2 mV, and small venous pressures decreased significantly. The onset of cardiovascular decompensation was associated with hyperpolarization (-53 +/- 3 mV), vasodilation, and return of venous pressure to control levels. Although direct electrical stimulation of the VSM and norepinephrine suffusion still produced constriction late in the hypotensive period, venoconstrictor responses to perivascular nerve stimulation failed progressively. This study indicates that failure of adrenergic neuromuscular transmission contributes significantly to the loss of compensatory VSM tone during hemorrhage.

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α-Band oscillations in intracellular membrane potentials of dentate gyrus neurons in awake rodents

Learning & Memory ◽

10.1101/lm.036269.114 ◽

2014 ◽

Vol 21 (12) ◽

pp. 656-661 ◽

Cited By ~ 4

Author(s):

Ross W. Anderson ◽

Ben W. Strowbridge

Keyword(s):

Dentate Gyrus ◽

Membrane Potentials ◽

Intracellular Membrane ◽

Α Band

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Comparison of the intracellular membrane potentials in crystalline lenses of various frogs

Comparative Biochemistry and Physiology Part A Physiology ◽

10.1016/0300-9629(84)90225-1 ◽

1984 ◽

Vol 77 (3) ◽

pp. 543-546

Author(s):

Y Okajima ◽

N Akaike

Keyword(s):

Membrane Potentials ◽

Intracellular Membrane

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Membrane Potentials Induced by External Rotating Electrical Fields

Electromagnetic Biology and Medicine ◽

10.3109/15368378709027728 ◽

1987 ◽

Vol 6 (1) ◽

pp. 49-69 ◽

Cited By ~ 1

Author(s):

Gunter Fuhr ◽

Rolf Hagedorn ◽

Roland Glaser ◽

Jan Gimsa ◽

Torsten Muller

Keyword(s):

Membrane Potentials ◽

Electrical Fields

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Primary involvement of K+ conductance in membrane resonance of trigeminal root ganglion neurons

Journal of Neurophysiology ◽

10.1152/jn.1988.59.1.77 ◽

1988 ◽

Vol 59 (1) ◽

pp. 77-89 ◽

Cited By ~ 29

Author(s):

E. Puil ◽

B. Gimbarzevsky ◽

I. Spigelman

Keyword(s):

Electrical Properties ◽

Channel Blocker ◽

Complex Impedance ◽

Membrane Potentials ◽

K Channel ◽

Bathing Medium ◽

Trigeminal Root ◽

Membrane Resonance ◽

Ganglion Neurons ◽

Impedance Magnitude

1. The complex impedances and impedance magnitude functions were obtained from neurons in in vitro slices of trigeminal root ganglia using frequency-domain analyses of intracellularly recorded voltage responses to specified oscillatory input currents. A neuronal model derived from linearized Hodgkin-Huxley-like equations was used to fit the complex impedance data. This procedure yielded estimates for membrane electrical properties. 2. Membrane resonance was observed in the impedance magnitude functions of all investigated neurons at their initial resting membrane potentials and was similar to that reported previously for trigeminal root ganglion neurons in vivo. Tetrodotoxin (10(-6) M), a Na+-channel blocker, applied in the bathing medium for 20 min produced only minor changes, if any, in the resonance, although gross impairment of Na+-spike electrogenesis was apparent in most of the neurons. Brief applications (1-5 min) of a K+-channel blocker, tetraethylammonium (TEA; 10(-2) M), increased the impedance magnitude and abolished, in a reversible manner, the resonant behavior. In all cases, the resonant frequency was decreased by TEA administration prior to total blockade of resonance. 3. The TEA-induced blockade of resonance was associated with decreases in the estimates of the membrane conductances, without significant alterations of input capacitance. A particularly large decrease was observed in Gr, the time-invariant resting conductance that includes a lumped leak conductance component. The voltage- and time-dependent conductance, GL, and associated relaxation time constant, tau u, also declined progressively during administration of TEA. 4. Systematic variations in the membrane potentials of trigeminal root ganglion neurons were produced by intracellular injections of long-lasting step currents with superposition of the oscillatory current stimuli, in order to assess the effects of TEA on the relationship of the electrical properties to the membrane potential. Applications of TEA led to a depolarizing shift in the dependence of the membrane property estimates, suggesting voltage-dependence of the effects of TEA on presumed K+ channels in the membrane. 5. These data suggest a primary involvement of K+ conductance in the genesis of membrane resonance. This electrical behavior or its ionic mechanism is a major modulator of the subthreshold electrical responsiveness of trigeminal root ganglion neurons.

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Progress and challenges of implantable neural interfaces based on nature-derived materials

Bioelectronic Medicine ◽

10.1186/s42234-021-00067-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Eugenio Redolfi Riva ◽

Silvestro Micera

Keyword(s):

Interface Design ◽

Specific Area ◽

Building Blocks ◽

Matrix Proteins ◽

Neural Interface ◽

Neural Interfaces ◽

Biomedical Science ◽

Chronic Inflammatory Response ◽

The Impact

AbstractNeural interfaces are bioelectronic devices capable of stimulating a population of neurons or nerve fascicles and recording electrical signals in a specific area. Despite their success in restoring sensory-motor functions in people with disabilities, their long-term exploitation is still limited by poor biocompatibility, mechanical mismatch between the device and neural tissue and the risk of a chronic inflammatory response upon implantation.In this context, the use of nature-derived materials can help address these issues. Examples of these materials, such as extracellular matrix proteins, peptides, lipids and polysaccharides, have been employed for decades in biomedical science. Their excellent biocompatibility, biodegradability in the absence of toxic compound release, physiochemical properties that are similar to those of human tissues and reduced immunogenicity make them outstanding candidates to improve neural interface biocompatibility and long-term implantation safety. The objective of this review is to highlight progress and challenges concerning the impact of nature-derived materials on neural interface design. The use of these materials as biocompatible coatings and as building blocks of insulation materials for use in implantable neural interfaces is discussed. Moreover, future perspectives are presented to show the increasingly important uses of these materials for neural interface fabrication and their possible use for other applications in the framework of neural engineering.

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