[Effect of doxofylline on calcium-activated potassium channels in human peripheral blood eosinophils in asthma]
Related Experiment Video
Updated: Aug 13, 2026
Three-Dimensional Cell Culture Models to Investigate the Epithelial Barrier in Eosinophilic Esophagitis
Published on: May 10, 2024
Bin Zhou1, Shao-xi Cai, Fei Zou
1Department of Respiratory Medicine, Nanfang Hospital, Nanfang Medical University, Guangzhou 510515, China.
Objective:
To study the effects of doxofylline on calcium-activated potassium (K(Ca)) channels of human peripheral blood eosinophils in asthma.
Methods:
Peripheral blood eosinophils from patients with asthma were isolated and divided equally into two groups, a control group and a doxofylline incubated group. The data were recorded using cell-attached configuration of patch-clamp technique and the kinetic changes of K(Ca) channels activated by 0.2 micromol/L platelet activating factor (PAF) were compared.
Results:
As compared with the control group, the open probability of the K(Ca) channels decreased from 0.135 +/- 0.021 to 0.044 +/- 0.018, the open time from (5.75 +/- 0.40) ms to (2.39 +/- 0.13) ms, while the close time increased from (2.17 +/- 0.50) ms to (23.73 +/- 2.50) ms in the doxofylline incubated group. The differences were significant between the two groups (all P < 0.05).
Conclusion:
Doxofylline could decrease the open probability of the channels as a result of both the shortening of open period and the prolongation of close time.
Related Concept Videos
01:18Antihypertensive Drugs: Action of Calcium Channel Blockers
01:19Antiasthma Drugs: Leukotriene Modifiers
Leukotriene modifiers work through two distinct mechanisms:
01:25Antiasthma Drugs: Mast Cell Stabilizers and Anti-IgE Drugs
Mast cell stabilizers, such as cromolyn (also known as sodium cromoglycate) and nedocromil (Tilade), are effective drugs in asthma management. These stabilizers hinder histamine release by skillfully obstructing the activation of mast cells and other cellular entities. Notably, they navigate this task without...
01:24Antiasthma Drugs: Methylxanthines
Theophylline is thought to inhibit phosphodiesterase enzymes, increasing intracellular levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). This rise in cAMP and cGMP concentrations stimulates cardiac function,...
01:25Antiasthma Drugs: β2-Adrenoceptor Agonists
One class of bronchodilators includes β2-adrenoceptor agonists. These agents target the β2-adrenoceptors located on bronchial smooth muscle cells. By stimulating these receptors, β2-agonists induce relaxation in these...
01:27Feedback Regulation of Calcium Concentration
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...