Dendroaspis natriuretic peptide (DNP), a newly-described natriuretic peptide, relaxes gastrointestinal smooth muscle. L-type calcium channel currents play an important role in regulating smooth muscle contraction. The effect of DNP on L-type calcium channel currents in gastrointestinal tract is still unclear. This study was designed to investigate the effect of DNP on barium current (I(Ba)) through the L-type calcium channel in gastric antral myocytes of guinea pigs and cGMP-pathway mechanism. The whole-cell patch-clamp technique was used to record L-type calcium channel currents. The content of cGMP in guinea pig gastric antral smooth muscle and perfusion solution was measured using radioimmunoassay. DNP markedly enhanced cGMP levels in gastric antral smooth muscle tissue and in perfusion medium. DNP concentration-dependently inhibited I(Ba) in freshly isolated guinea pig gastric antral circular smooth muscle cells (SMCs) of guinea pigs. DNP-induced inhibition of I(Ba) was partially blocked by LY83583, an inhibitor of guanylate cyclase. KT5823, a cGMP-dependent protein kinase (PKG) inhibitor, almost completely blocked DNP-induced inhibition of I(Ba). However, DNP-induced inhibition of I(Ba) was potentiated by zaprinast, an inhibitor of cGMP-sensitive phosphodiesterase. Taken together, DNP inhibits L-type calcium channel currents via pGC-cGMP-PKG-dependent signal pathway in gastric antral myocytes of guinea pigs.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.regpep.2010.05.015DOI Listing

Publication Analysis

Top Keywords

l-type calcium
24
calcium channel
24
smooth muscle
20
gastric antral
20
channel currents
16
natriuretic peptide
12
guinea pigs
12
dnp-induced inhibition
12
inhibition iba
12
dendroaspis natriuretic
8

Similar Publications

To encode continuous sound stimuli, the inner hair cell (IHC) ribbon synapses utilize calcium-binding proteins (CaBPs), which reduce the inactivation of their Ca1.3 calcium channels. Mutations in the gene underlie non-syndromic autosomal recessive hearing loss DFNB93.

View Article and Find Full Text PDF

The global incidence of mortality due to heart failure (HF) is on the rise, presenting a significant challenge in various regions, including Japan. There is an urgent need for innovative prevention and treatment strategies to address this issue. Traditional medicine, particularly Japanese Kampo medicine (JKM), has been proposed as a potential therapeutic approach and has undergone examination in clinical trials related to HF.

View Article and Find Full Text PDF

Acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS), result from pulmonary edema and alveolar-capillary barrier disruption due to inflammation, often triggered by conditions like sepsis. Sepsis-induced ALI (SALI) involves extensive damage to vascular endothelium and alveolar epithelium, leading to respiratory failure. Our study explores ferroptosis, an iron-dependent cell death pathway, and calcium dysregulation in SALI.

View Article and Find Full Text PDF

Regulation of SR and mitochondrial Ca signaling by L-type Ca channels and Na/Ca exchanger in hiPSC-CMs.

Cell Calcium

December 2024

Cardiac Signaling Center of USC, MUSC and Clemson University, 68 President St BEB 306, Charleston, SC 29425, USA. Electronic address:

Rationale & Methods: While signaling of cardiac SR by surface membrane proteins (I & I) is well studied, the regulation of mitochondrial Ca by plasmalemmal proteins remains less explored. Here we have examined the signaling of mitochondria and SR by surface-membrane calcium-transporting proteins, using genetically engineered targeted fluorescent probes, mito-GCamP6 and R-CEPIA1er.

Results: In voltage-clamped and TIRF-imaged cardiomyocytes, low Na induced SR Ca release was suppressed by short pre-exposures to ∼100 nM FCCP, suggesting mitochondrial Ca contribution to low Na triggered SR Carelease.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!