Synergistic increase in Ca2+ produced by A1 adenosine and muscarinic receptor activation via a pertussis-toxin-sensitive pathway in epithelial cells of the rabbit ciliary body

Experimental Eye Research
N A Farahbakhsh, M C Cilluffo

Abstract

The combined effects of adenosine and acetylcholine on the intracellular free-Ca2+ concentration in nonpigmented epithelial cells of the rabbit ciliary body were investigated using fura-2 fluorescence-ratio imaging. Acetylcholine (10 microM) by itself produced a modest increase in [Ca2+]i. Acetylcholine in combination with adenosine, or with the A1-specific agonists N6-cyclohexyl-adenosine, N6-cyclopentyl-adenosine and (R)-N6-(2-phenyl-1-methylethyl)-adenosine (0.1-1 microM), induced a massive increase in [Ca2+]i, which could be blocked by the A1-specific antagonist 8-cyclopentyl-1,3-dipropylxanthine. However, the A2-specific agonist 2-[(p-2-carboxyethyl)-phenethylamino]-5'-N-ethylcarboxamide-ade nos ine and the antagonist 3,7-dimethyl-1-(2-propynyl)xanthine were without effect. Incubation of the tissue with pertussis toxin did not alter the response to ACh alone but eliminated the synergistic effect of adenosine (or of epinephrine). It was concluded that in the epithelial cells of the rabbit ciliary body, adenosine and epinephrine synergistically potentiate the rise in [Ca2+]i produced by ACh. This potentiation appears to occur via a pertussis-toxin-sensitive pathway, perhaps through G(i).

Citations

Jul 8, 1998·Proceedings of the National Academy of Sciences of the United States of America·K HirataM L Sears
Oct 12, 2010·Progress in Retinal and Eye Research·Makoto Araie, Chihiro Mayama
Nov 14, 2007·Experimental Eye Research·Maria C EdmanJ Peter Gierow
Nov 5, 2003·Journal of Experimental Zoology. Part A, Comparative Experimental Biology·Nasser A Farahbakhsh
Mar 23, 2005·Experimental Eye Research·David J CollisonJulie Sanderson
Jul 1, 1997·In Vitro Cellular & Developmental Biology. Animal·M C CilluffoG L Fain
Dec 14, 2004·American Journal of Physiology. Cell Physiology·Mike O KarlM M Civan
Mar 10, 1999·The American Journal of Physiology·C H MitchellM M Civan
Aug 16, 2000·American Journal of Physiology. Cell Physiology·M C CilluffoN A Farahbakhsh
Dec 22, 2020·PloS One·Mohammad ShahidullahNicholas Anthony Delamere
Nov 14, 1997·The American Journal of Physiology·D A CarréM M Civan

❮ 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.