hyperpolarization

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hyperpolarization

 [hi″per-po″ler-ĭz-a´shun]
any increase in the amount of electrical charge separated by the cell membrane and hence in the strength of the membrane potential. In cardiology this is the process by which an electrical fiber, at the end of phase 3 repolarization, becomes more negative than usual.

hy·per·po·lar·i·za·tion

(hī'pĕr-pō'lăr-i-zā'shŭn),
An increase in polarization of membranes of nerves or muscle cells; the reverse change from that associated with excitatory action.

hyperpolarization

/hy·per·po·lar·iza·tion/ (hi″per-po″ler-ĭ-za´shun) any increase in the amount of electrical charge separated by the cell membrane, and hence in the strength of the transmembrane potential.

hy·per·po·lar·i·za·tion

(hī'pĕr-pō'lăr-ī-zā'shŭn)
An increase in polarization of membranes of nerves or muscle cells, which makes the cell less sensitive to any stimulus; the reverse change from that associated with excitatory action.

hyperpolarization

A change in the value of the resting membrane potential towards a more negative value. The inside of the cell becomes more negative than the outside. Hyperpolarization is inhibitory because the membrane potential moves away from the neuron's threshold at which an action potential could occur. Example: the retinal photoreceptor potentials when stimulated by light. See depolarization; receptor potential; resting membrane potential; synapse.

hy·per·po·lar·i·za·tion

(hī'pĕr-pō'lăr-ī-zā'shŭn)
Increased polarization of membranes of nerves or muscle cells.

hyperpolarization

an increase in the amount of electrical charge on either side of a cell membrane so that there is an increase in the electric potential across the membrane.
References in periodicals archive ?
The mechanism appears to be mediated by the opening of potassium channels and subsequent membrane hyperpolarisation rather than an [alpha]2-agonist effect.
m] hyperpolarisation [21] which in turn is accompanied by increasing superoxide anion formation [22].
Guiding this assembling is the conception that only by teaming together key areas of expertise, can hyperpolarisation s promises be realized.
The use of electric stimulation in a region of the nervous system will trigger an action potential in an axon, while at the same time causing hyperpolarisation of the cell body.
The analgesic action of intrathecal [alpha]2 adrenoreceptors agonist is by depressing the release of C-fiber transmitters which explain the prolongation of the sensory block and by hyperpolarisation of postsynaptic dorsal horn neurons which explain the prolongation of the motor block.
following its chemical gradient, cell membrane hyperpolarisation, [Cl.
In essence it uses the periods of vigorous high-frequency activity to identify the 'up' states of neuronal depolarisation and periods of almost no high-frequency activity to identify the 'down' states of neuronal hyperpolarisation.
The prolonged action of Dexmedetomidine may be produced by the membrane hyperpolarisation due to opening of the potassium channels, which increases the sodium channel blocking property of local anaesthetic.
Intrathecal Fentanyl inhibits afferent synaptic transmission via C and A fibres, and also has direct postsynaptic effect with hyperpolarisation and reduced neuronal activity causing prolongation of postoperative pain relief.
The anaesthetic and analgesic requirement get reduced to much extent by the use of alpha-2 adrenergic agonist dexmedetomidine as an adjuvant, because of its analgesic properties and augmentation of local anaesthetic effects as they cause hyperpolarisation of nerve tissues by alteration of transmembrane potential and ion conductance at locus coeruleus in the brain stem.
2+]) and hyperpolarisation of the smooth-muscle cell potassium (K+) to cause relaxation of the arteries with a decrease in venous drainage.