Vasoactive intestinal polypeptide receptor antagonism enhances the vagally induced increase in cardiac interval of the rat atrium in vitro

Experimental Physiology
Kieran Hogan, F Markos

Abstract

The effect of vasoactive intestinal polypeptide (VIP) receptor antagonism on preganglionic vagal electrical stimulation and on vagal postganglionic activation using nicotine and 1,1-dimethyl-4-phenylpiperazinium iodide on cardiac interval was evaluated in the isolated innervated rat right atrium. The vagus was stimulated at 4, 8, 16 and 32 Hz, pulse duration 1 ms, 20 V, for 30 s. All experiments were carried out in the presence of atenolol (4 microM). Vagal stimulation caused a frequency-dependent increase in cardiac interval which was amplified significantly at each frequency, except at 32 Hz, following application of the VIP receptor antagonist VIP(6-28) at 2 nM in 15 rats. Application of the ganglionic antagonist hexmethonium (28 microM, n = 7 rats) prior to 2 nM VIP(6-28) abolished this effect. Increasing the concentration of VIP(6-28) 10-fold to 20 nM did not result in a greater increase in cardiac interval than that obtained at 2 nM. Nicotine (0.1, 0.3, 0.5, 1.0 and 2.0 mM) increased cardiac interval by direct activation of postganglionic vagal fibres, but 2 nM VIP(6-28) did not affect the nicotine concentration response (n = 6 rats). 1,1-Dimethyl-4-phenylpiperazinium iodide (25, 50, 100 and 200 microM; n = 6 rats) was al...Continue Reading

References

Dec 21, 2000·Cardiovascular Research·R J Henning, D R Sawmiller
Oct 3, 2003·Cell and Tissue Research·R J RichardsonC R Anderson
Jun 9, 2004·Autonomic Neuroscience : Basic & Clinical·Catherine Sweeney, Farouk Markos
Aug 24, 2004·Current Pharmaceutical Design·L A Van Geldre, R A Lefebvre

❮ Previous
Next ❯

Citations

Apr 10, 2016·The Journal of Physiology·Beth A HabeckerCrystal M Ripplinger
Sep 21, 2013·Circulation. Arrhythmia and Electrophysiology·Yutao XiJie Cheng

❮ 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.