Two opposing roles of 4-AP-sensitive K+ current in initiation and invasion of spikes in rat mesencephalic trigeminal neurons

Journal of Neurophysiology
Mitsuru SaitoYoungnam Kang

Abstract

The axon initial segment plays important roles in spike initiation and invasion of axonal spikes into the soma. Among primary sensory neurons, those in the mesencephalic trigeminal nucleus (MTN) are exceptional in their ability to initiate soma spikes (S-spikes) in response to synaptic inputs, consequently displaying two kinds of S-spikes, one caused by invasion of an axonal spike arising from the sensory receptor and the other initiated by somatic inputs. We investigated where spikes are initiated in such MTN neurons and whether there are any differences between the two kinds of S-spikes. Simultaneous patch-clamp recordings from the soma and axon hillock revealed a spike-backpropagation from the spike-initiation site in the stem axon to the soma in response to 1-ms somatic current pulse, which disclosed the delayed emergence of S-spikes after the current-pulse offset. These initiated S-spikes were smaller in amplitude than S-spikes generated by stimulation of the stem axon; however, 4-AP (< or =0.5 mM) eliminated the amplitude difference. Furthermore, 4-AP dramatically shortened the delay in spike initiation without affecting the spike-backpropagation time in the stem axon, whereas it substantially prolonged the refractory per...Continue Reading

References

Nov 1, 1992·Trends in Neurosciences·I Segev
Oct 1, 1991·Physiological Reviews·J Patlak
Jun 1, 1988·Neuroscience·B Rudy
Mar 1, 1970·The American Journal of Anatomy·C F Hinrichsen, L M Larramendi
Jul 20, 1981·Brain Research·T KayaharaS Sakashita
Jan 1, 1994·European Biophysics Journal : EBJ·A BertoliF Conti
Oct 1, 1995·Trends in Neurosciences·A KoltaP Clavelou
Jun 15, 1996·The Journal of Physiology·S H HeinemannO Pongs
Dec 1, 1996·Trends in Neurosciences·J MagistrettiE Wanke
Feb 11, 1998·The Journal of Physiology·G StuartB Sakmann
Apr 16, 1998·Histochemistry and Cell Biology·N E LazarovC Pilgrim
Jul 22, 1999·Annals of the New York Academy of Sciences·W A CoetzeeB Rudy
Aug 28, 1999·The Journal of Biological Chemistry·Y G KwakM M Tamkun
Sep 14, 1999·Journal of Neurophysiology·C M PedroarenaF R Morales
Feb 5, 2002·The Journal of Physiology·Sergey V SmirnovPhilip I Aaronson
May 7, 2002·Nature Neuroscience·Costa M Colbert, Enhui Pan
Jun 4, 2002·The Journal of Physiology·Patricia A GlazebrookDiana L Kunze
Dec 19, 2002·Neuroreport·Hisayoshi Ishii, Youngnam Kang
Sep 12, 2003·Journal of Neurophysiology·Luigi CatacuzzenoFabio Franciolini
Dec 3, 1957·The Journal of Physiology·J S COOMBSJ C ECCLES

❮ Previous
Next ❯

Citations

Dec 17, 2009·The Neuroscientist : a Review Journal Bringing Neurobiology, Neurology and Psychiatry·Brian D ClarkBernardo Rudy
Oct 5, 2007·Brain Research Reviews·Nikolai E Lazarov
Oct 12, 2007·Journal of Neurophysiology·Youngnam KangToshihiro Hirai
Oct 14, 2019·Neuroscience Bulletin·Ning YinZhongfeng Wang
Feb 9, 2018·Frontiers in Cellular Neuroscience·Kayo NishimuraYoungnam Kang

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.