Video Experimental Relacionado

Updated: Jul 6, 2026

Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells

Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells

Published on: July 16, 2013

Coordinación de los patrones de señalización de Ca2+ inducidos por agonistas por NAADP en las células acinares

J M Cancela¹, G C Churchill, A Galione

¹Department of Pharmacology, University of Oxford, UK. j.m.cancela@liverpool.ac.uk

|March 17, 1999

Resumen

El fosfato de adenina dinucleótido de ácido nicotínico (NAADP) desencadena diversas señales de calcio en las células pancreáticas, a diferencia de otros mensajeros. Esto sugiere que el NAADP actúa como un nuevo mensajero intracelular en los mamíferos.

Área de la Ciencia:

Biología celular Biología celular.
La bioquímica es la bioquímica.
Fisiología Fisiología Fisiología.

Sus antecedentes:

Las hormonas y los neurotransmisores modulan la liberación de calcio intracelular (Ca2+), creando patrones de señalización específicos.
El trisfosfato de inositol (InsP3) y la adenosina cíclica 5'-difosfato-ribosa (cADPR) son conocidos mensajeros de Ca2+ que activan los receptores de InsP3 y de ryanodina, respectivamente.
Los mensajeros existentes no explican completamente la complejidad de señalización de Ca2+ inducida por la colecistoquinina (CCK) en las células acinares pancreáticas.

Objetivo del estudio:

Para investigar el papel del fosfato de adenina dinucleótido de ácido nicotínico (NAADP) como un potencial mensajero de Ca2+ en las células acinares pancreáticas.
Para comparar los efectos de movilización de Ca2+ de NAADP con InsP3 y cADPR.
Para aclarar el mecanismo por el cual se regulan las señales de Ca2+ evocadas por CCK.

Principales métodos:

Medición de las concentraciones intracelulares de Ca2+ en las células acinares pancreáticas.
Aplicación de NAADP, cADPR e InsP3 para estimular la liberación de Ca2+.
Inactivación selectiva de las señales de Ca2+ evocadas por CCK utilizando diferentes concentraciones de NAADP.

Principales resultados:

NAADP desencadenó diversas respuestas de Ca2+, incluyendo picos de corta y larga duración, distintos de InsP3 y cADPR.
Las células acinares pancreáticas mostraron una mayor sensibilidad al NAADP en comparación con el cADPR o el InsP3.
Las concentraciones más altas de NAADP inhibían selectivamente la señalización de Ca2+ inducida por CCK.

Conclusiones:

La NAADP funciona como un potente mensajero de movilización de Ca2+ en las células acinares pancreáticas.
La señalización mediada por NAADP es distinta de las vías InsP3 y cADPR y puede modularlas.
NAADP representa un nuevo mensajero intracelular potencialmente involucrado en la señalización celular de los mamíferos.

Más Videos Relacionados

Dissection of Local Ca2+ Signals in Cultured Cells by Membrane-targeted Ca2+ Indicators

Dissection of Local Ca²⁺ Signals in Cultured Cells by Membrane-targeted Ca²⁺ Indicators

Published on: March 22, 2019

Imaging Initial Ca2+ Microdomains in Primary T Cells

Imaging Initial Ca²⁺ Microdomains in Primary T Cells

Published on: October 4, 2024

Videos de Conceptos Relacionados

Amplifying Signals via Second Messengers

Amplifying Signals via Second Messengers

Many receptor binding ligands are hydrophilic; they do not cross the cell membrane but bind to cell-surface receptors. Thus, their message must be relayed by second messengers present in the cell cytoplasm. There are several second messenger pathways, each with its own way of relaying information. For example, the G protein-coupled receptors can activate both phosphoinositol and cyclic AMP (cAMP) second messenger pathways. The phosphoinositol pathway is active when the receptor induces...

GPCRs Regulate Adenylyl Cylase Activity

GPCRs Regulate Adenylyl Cylase Activity

Some GPCRs transmit signals through adenylyl cyclase (AC), a transmembrane enzyme. AC helps synthesize second messenger cyclic adenosine monophosphate (cAMP). AC catalyzes cyclization reaction and converts ATP to cAMP by releasing a pyrophosphate. The pyrophosphate is further hydrolyzed to phosphate by the enzyme pyrophosphatase, which drives cAMP synthesis to completion. However, cAMP is rapidly degraded to 5′ AMP by the enzymes phosphodiesterase (PDE), preventing overstimulation of cells.
Two...

cAMP-dependent Protein Kinase Pathways

cAMP-dependent Protein Kinase Pathways

Cyclic Adenosine Monophosphate (cAMP) is an essential second messenger that activates protein kinase A (PKA) and regulates various biological processes. A single epinephrine molecule binds to GPCR and activates several heterotrimeric G proteins, each stimulating multiple adenylyl cyclase, amplifying the signal, and synthesizing large numbers of cAMP molecules. Small changes in cAMP concentration affect PKA activity. The binding of four cAMP molecules induces a conformational change in PKA,...

IP3/DAG Signaling Pathway

IP3/DAG Signaling Pathway

Membrane lipids such as phosphatidylinositol (PI) are precursors for several membrane-bound and soluble second messengers. Specific kinases phosphorylate PI and produce phosphorylated inositol phospholipids. One such inositol phospholipids are the phosphatidylinositol-4,5 bisphosphate [PI(4,5)P2], present in the inner half of the lipid bilayer. Upon ligand binding, GPCR stimulates Gq proteins to turn on phospholipase Cꞵ. Activated phospholipase Cꞵ cleaves PI(4,5)P2 and produces two-second...

Feedback Regulation of Calcium Concentration

Feedback Regulation of Calcium Concentration

Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...

Calmodulin-dependent Signaling

Calmodulin-dependent Signaling

Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...