Congo red modulates ACh-induced Ca2+ oscillations in single pancreatic acinar cells of mice

Abstract

Aim: Congo red, a secondary diazo dye, is usually used as an indicator for the presence of amyloid fibrils. Recent studies show that congo red exerts neuroprotective effects in a variety of models of neurodegenerative diseases. However, its pharmacological profile remains unknown. In this study, we investigated the effects of congo red on ACh-induced Ca 2+ oscillations in mouse pancreatic acinar cells in vitro. Methods: Acutely dissociated pancreatic acinar cells of mice were prepared. A U-tube drug application system was used to deliver drugs into the bath. Intracellular Ca 2+ oscillations were monitored by whole-cell recording of Ca 2+ -activated Cl -currents and by using confocal Ca 2+ imaging. For intracellular drug application, the drug was added in pipette solution and diffused into cell after the wholecell configuration was established. Results: Bath application of ACh (10 nmol/L) induced typical Ca 2+ oscillations in dissociated pancreatic acinar cells. Addition of congo red (1, 10, 100 µmol/L) dose-dependently enhanced Ach-induced Ca 2+ oscillations, but congo red alone did not induce any detectable response. Furthermore, this enhancement depended on the concentrations of ACh: congo red markedly enhanced the Ca 2+ oscillations induced by ACh (10-30 nmol/L), but did not alter the Ca 2+ oscillations induced by ACh (100-10000 nmol/L). Congo red also enhanced the Ca 2+ oscillations induced by bath application of IP 3 (30 µmol/L). Intracellular application of congo red failed to alter ACh-induced Ca 2+ oscillations. Conclusion: Congo red significantly modulates intracellular Ca 2+ signaling in pancreatic acinar cells, and this pharmacological effect should be fully considered when developing congo red as a novel therapeutic drug.

Cannabinoid receptor subtype 2 (CB2R) agonist, GW405833 reduces agonist-induced Ca2+ oscillations in mouse pancreatic acinar cells

“…Under the acutely dissociated acinar cell protocol, the isolated cells exhibited a typical kidney shape with secretion granules in the central area of the cells ( Supplemental Fig. 2 ), suggesting the purity of the acinar cells as previously reported 13 15 17 . Figure 1A shows the results of the immunoblot assays, illustrating that a CB 2 -positive band was detected (at ~40 kD) in both the spleen and striatal tissues of WT and CB 1 -KO (CB 1 −/− ), while the densities of this band in CB 2 -KO mice (CB 2 −/− ) were substantially reduced in CB 2 -rich spleen tissues and almost undetectable in striatal tissues.…”

“…Acute isolated pancreatic cells were prepared as previously described 13 14 15 . In brief, pancreatic glands were taken from isoflurane-anesthetized mice, and fragments of the tissue were minced and digested using collagenase (200 U/mL, 25–30 min, 37 °C; Wako Pure Chemicals, Osaka, Japan) in the presence of 1-mM Ca 2+ .…”

In situ nano-fibrillation of microinjection molded poly(lactic acid)/poly(ε-caprolactone) blends and comparison with conventional injection molding

“…Below are several examples. [20][21][22] Huang et al 20 prepared polypropylene (PP) products with thickness of 0.7 mm (m-PP) and 3.5 mm (m-PP) through microinjection molding and conventional injection molding, respectively. The results showed that compared with m-PP products, tensile strength and storage modulus (40 C) of m-PP increases by 67% and 48% respectively.…”

Heterogeneity of cannabinoid ligand-induced modulations in intracellular Ca2+ signals of mouse pancreatic acinar cells in vitro

“…Additionally, C57BL/6J WT, CB 1 R KO [5], and CB 2 R KO mice [6] of similar ages and gender on a C57BL/6J genetic background were used to determine the targets of cannabinoid ligands. Pancreatic cells were acutely isolated as previously described [7][8][9]. In brief, pancreatic glands were taken from isoflurane-anesthetized mice, and fragments of the pancreatic tissue were minced and digested using collagenase (200 U/mL, 25-30 min, 37°C; Wako Pure Chemicals, Osaka, Japan) in the presence of 1 mM Ca 2+ .…”