Related Experiment Video
Updated: Jun 9, 2026
07:51
Mesenteric Artery Contraction and Relaxation Studies Using Automated Wire Myography
Published on: September 22, 2011
Ghrelin signaling in human mesenteric arteries
D Z Dimitrova1, S D Dimitrov, I Iliev
1Institute of Biophysics, Bulgarian Academy of Sciences, Sofia, Bulgaria.
Summary
Ghrelin enhances human mesenteric artery contraction via a novel pathway involving Src kinase, MEK, and thromboxane A2. This study identifies new mediators in the ghrelin signaling pathway.
Area of Science:
- Vascular Physiology
- Molecular Signaling
- Gastrointestinal Hormones
Background:
- Ghrelin is known to influence vascular tone.
- The precise signaling mechanisms of ghrelin in human mesenteric arteries remain incompletely understood.
Purpose of the Study:
- To elucidate the novel signaling pathway and mediators involved in ghrelin-induced contraction of human mesenteric arteries.
Main Methods:
- Isometric wire myography was used to measure arterial contractile force.
- Whole-cell patch clamp electrophysiology was performed on isolated smooth muscle cells.
- Pharmacological inhibitors and specific receptor antagonists were employed to dissect the signaling cascade.
Main Results:
- Ghrelin (100 nmol) abolished outward potassium currents via iberiotoxin-sensitive calcium-activated potassium channels.
- Ghrelin dose-dependently increased mesenteric artery contraction.
- This effect was mediated by Src kinase, mitogen-activated protein kinase kinase (MEK), cyclooxygenase 1, and a T prostanoid receptor agonist, likely thromboxane A2.
Conclusions:
- Ghrelin stimulates contraction in human mesenteric arteries through a novel signaling pathway.
- Key components of this pathway include Src kinase, MEK, cyclooxygenase 1, and thromboxane A2.
Related Concept Videos
01:30Regulation of Food Intake
Short-term regulation of food intake primarily involves neural signals from the gastrointestinal (GI) tract, blood nutrient levels, and GI tract hormones. Communication between the gut and brain via vagal nerve fibers plays a significant role in evaluating the contents of the gut. Clinical studies have shown that protein ingestion produces a more prolonged response in these nerve fibers compared to an equivalent amount of glucose. Additionally, the activation of stretch receptors caused by GI...
01:09GPCRs 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...
Two...
01:27Transducer Mechanism: Enzyme-Linked Receptors
Enzyme-linked receptors are cell-surface receptors acting as an enzyme or associating with an enzyme intracellularly. They make excellent drug targets. Drugs can bind to the extracellular ligand-binding domain or directly affect their enzymatic domain and alter their activity.
Major types that are helpful drug targets include:
Major types that are helpful drug targets include: