hyperpolarization


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Related to hyperpolarization: hypopolarization, Graded potential

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.

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.
References in periodicals archive ?
In both the vertebrate rod and cone and the scallop systems, current inhibition is due to photoreceptor hyperpolarization, albeit via different mechanisms.
- Interference with the establishment of hyperpolarization in the neuronal cell membrane, allowing for prolonged cell membrane depolarization and accordingly stronger nerve impulse.
Adiponectin, via activation of the AMPK, inhibited GnRH secretion and caused a hyperpolarization of plasma membrane potentials and reduction of calcium influx in GT1-7 mouse hypothalamic GnRH-produced neurons [56].
Moreover, tyrosine kinase inhibitors activate the maxi-K[Ca.sup.2+](BK[Ca.sup.2+]) channels in the bovine trabecular veins and that hyperpolarization caused by the potassium efflux of the trabecular cells can lead to the relaxation of the trabecular meshwork to facilitate the outflow and passage of AH to Schlemm's channel [8-10].
Specifically, both stimulation of the vibrissae on the snout (whiskers) of mice and auditory stimulation evoked hyperpolarization in V1 [8].
The importance of consolidating and reifying this norm, in its most salient legal context, cannot be overstated at a time when hyperpolarization between the major parties dominates national politics and is at its most severe in our lifetime.
Hence, it easily penetrates the meninges.[11] They also cause augmentation of local anesthetic effects as they cause hyperpolarization of nerve tissues by altering transmembrane potential and ion conductance at locus coeruleus in the brainstem.[12] The increase in analgesic action of local anesthetics by the use of a-2 agonists in the epidural space may be related to the reduction of the systemic absorption of the local anesthetic effect caused by local vasoconstrictor subtypes mediated by the C2 in smooth muscle and venous epidural plexus.[13]
The sedative effect of dexmedetomidine is due to the hyperpolarization of noradrenergic neurons in the locus ceruleous of the brain stem.
Among the topics are obtaining gas phase NMR parameters from molecular beam and high-resolution microwave spectroscopy, gas phase NMR for studying chemical reactions: kinetics and product identification, accurate non-relativistic calculations of NMR shielding constants, rovibrational and temperature effects in theoretical studies of NMR parameters, and optical hyperpolarization of noble gases for medical imaging.
The connection of endothelial BK to B2 receptors leads to the production of nitric oxide (NO), formation of prostacyclin, elevation of intracellular [Ca.sup.2+] and formation of the hyperpolarization factor, which causes vasodilation and increased vascular permeability.
(27) This shift inverts the polarity of currents activated by [gamma]-amino butyric acid (GABA) and glycine, such that GABA and glycine cause depolarization, rather than hyperpolarization, in these secondary sensory neurons.