Cultured melanotrophs of the adult rat pituitary possess a voltage-activated fast transient outward current.

The Journal of Physiology
S J Kehl

Abstract

1. Whole-cell voltage-clamp recordings were made from cultured melanotrophs obtained from adult rats and maintained in vitro using conventional cell culture procedures. 2. The outward current recorded in the presence of Na+ and Ca2+ channel blockers was normally comprised of two components: a slowly activating, slowly inactivating current (IK(s] and a fast transient current (IK(f]. The selective blockade of IK(s) by 20 mM-tetraethylammonium (TEA+) allowed the properties of IK(f) to be analysed in isolation. 3. The activation threshold for IK(f) was normally between -20 and -10 mV and the current-voltage relationship was linear. At positive potentials the decay of IK(f) was well fitted by a single exponential having a time constant of 20-35 ms. At -70 mV recovery from inactivation was best described by a single-exponential function with a time constant of 20-40 ms. IK(f) was fully activatable at -60 mV and was fully inactivated at -10 mV; the half-inactivation potential was approximately -25 mV. 4. Since IK(f) was reduced by raising the external concentration of K+, was blocked by Ba2+ and Cs+, and persisted in Ca2+-free medium it is attributed to a voltage-activated K+ conductance. The amplitude of IK(f) was unaffected either b...Continue Reading

Citations

May 31, 1993·Annals of the New York Academy of Sciences·J A ValentijnL Cazin
Mar 1, 1992·Pflügers Archiv : European journal of physiology·R Schneggenburger, J López-Barneo
Nov 14, 1997·The Journal of General Physiology·M YoshinoC Y Kao

❮ 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.