Calcium mobilization and influx during the biphasic cytosolic calcium and secretory responses in agonist-stimulated pituitary gonadotrophs.

Archives of Biochemistry and Biophysics
S IzumiK J Catt

Abstract

Stimulation of enriched pituitary gonadotrophs by gonadotropin-releasing hormone (GnRH) elicits dose-dependent biphasic elevations of cytosolic calcium ([Ca2+]i) and luteinizing hormone (LH) release, with rapid initial peaks followed by sustained plateaus during continued exposure to the agonist. A potent GnRH-antagonist, [N-acetyl-D-p-Cl-Phe1,2,D-Trp3,D-Lys6,D-Ala10]GnRH, prevented the biphasic [Ca2+]i and LH responses when added before GnRH, and rapidly abolished both responses to GnRH when added during the plateau phase. In low Ca2+ medium the LH peak responses to GnRH were reduced and the subsequent sustained responses were almost completely abolished; reduction of extracellular Ca2+ during exposure to GnRH caused a prompt decline of LH release. The initial [Ca2+]i peak is derived largely from intracellular calcium mobilization with a partial contribution from calcium influx, while the sustained phase is dependent on the entry of extracellular Ca2+ through both L-type and dihydropyridine-insensitive channels. The presence of L-type voltage-sensitive calcium channels (VSCC) in pituitary gonadotrophs was indicated by the ability of elevated extracellular [K+] to stimulate calcium influx and LH release, and the sensitivity of ...Continue Reading

References

Dec 1, 1987·Proceedings of the National Academy of Sciences of the United States of America·G GuillemetteK J Catt
Jan 29, 1986·Biochemical and Biophysical Research Communications·L KieselB Runnebaum
Oct 1, 1988·The American Journal of the Medical Sciences·P F Blackmore
Jul 15, 1988·Biochemical and Biophysical Research Communications·K TasakaK J Catt
Dec 18, 1981·Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences·R H MichellJ A Creba
Feb 1, 1984·Molecular and Cellular Endocrinology·J L TurgeonD A Walsh

❮ Previous
Next ❯

Citations

Nov 30, 1990·The Journal of Steroid Biochemistry and Molecular Biology·P D GuptaA G Reddy
Mar 1, 1992·The Journal of Steroid Biochemistry and Molecular Biology·S S StojilkovićK J Catt
Nov 1, 1990·Proceedings of the National Academy of Sciences of the United States of America·S S StojilkovićK J Catt
Oct 1, 1995·Journal of Neuroendocrinology·S S Stojilkovic, K J Catt
Apr 1, 2009·General and Comparative Endocrinology·Grégoy Y BédécarratsRamesh Ramachandran
Jul 23, 1998·Physiological Reviews·J Vanecek
Oct 17, 1998·The Journal of Peptide Research : Official Journal of the American Peptide Society·V S AnanthanarayananK S Brimble

❮ 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.