Histamine activates an intracellular Ca signal in normal human lung fibroblast WI-38 cells.

Histamine is an inflammatory mediator that can be released from mast cells to induce airway remodeling and cause persistent airflow limitation in asthma. In addition to stimulating airway smooth muscle cell constriction and hyperplasia, histamine promotes pulmonary remodeling by inducing fibroblast proliferation, contraction, and migration. It has long been known that histamine receptor 1 (H1R) mediates the effects of histamine on human pulmonary fibroblasts through an increase in intracellular Ca concentration ([Ca]), but the underlying signaling mechanisms are still unknown.

Type 2 Diabetes Alters Intracellular Ca Handling in Native Endothelium of Excised Rat Aorta.

An increase in intracellular Ca concentration ([Ca]) plays a key role in controlling endothelial functions; however, it is still unclear whether endothelial Ca handling is altered by type 2 diabetes mellitus, which results in severe endothelial dysfunction. Herein, we analyzed for the first time the Ca response to the physiological autacoid ATP in native aortic endothelium of obese Zucker diabetic fatty (OZDF) rats and their lean controls, which are termed LZDF rats. By loading the endothelial monolayer with the Ca-sensitive fluorophore, Fura-2/AM, we found that the endothelial Ca response to 20 µM and 300 µM ATP exhibited a higher plateau, a larger area under the curve and prolonged duration in OZDF rats.

Automated Intracellular Calcium Profiles Extraction from Endothelial Cells Using Digital Fluorescence Images.

Endothelial cells perform a wide variety of fundamental functions for the cardiovascular system, their proliferation and migration being strongly regulated by their intracellular calcium concentration. Hence it is extremely important to carefully measure endothelial calcium signals under different stimuli. A proposal to automate the intracellular calcium profiles extraction from fluorescence image sequences is presented.

Lung Beractant Increases Free Cytosolic Levels of Ca2+ in Human Lung Fibroblasts.

Beractant, a natural surfactant, induces an antifibrogenic phenotype and apoptosis in normal human lung fibroblasts (NHLF). As intracellular Ca2+ signalling has been related to programmed cell death, we aimed to assess the effect of beractant on intracellular Ca2+ concentration ([Ca2+]i) in NHLF in vitro. Cultured NHLF were loaded with Fura-2 AM (3 μM) and Ca2+ signals were recorded by microfluorimetric techniques.