Involvement of cytoskeletal integrity in the regulation of Cl- and amylase secretion from rat parotid acinar cells

• Published in: Biomedical Research Vol. 29; no. 3; pp. 131 - 139
• Main Authors: KONGO, Hiroyasu, HIRONO, Chikara, SUGITA, Makoto, Iwasa, Yoshiko, SHIBA, Yoshiki
• Format: Journal Article
• Language: English
• Published: Japan Biomedical Research Press 2008; Japan Science and Technology Agency
• Subjects: Amylases - metabolism; Animals; Carbachol - pharmacology; Chlorides - metabolism; Colchicine - pharmacology; Cytochalasin D - pharmacology; Cytoskeleton - metabolism; Male; Parotid Gland - cytology; Parotid Gland - enzymology; Parotid Gland - metabolism; Rats; Rats, Wistar
• ISSN: 0388-6107; 1880-313X
• DOI: 10.2220/biomedres.29.131

The cytoskeleton serves as a signal modulator for Ca2+ and cAMP-regulated cell functions including the secretion of ions and granule contents. The interaction between Ca2+ and cAMP signaling systems potentiates amylase secretion and suppresses Cl- secretion in the parotid glands. In this study, we investigated the role of the cytoskeleton in the modulation of Cl- and amylase secretion from rat parotid acinar cells upon activation of each intracellular signaling system and their interaction. Cytochalasin D markedly inhibited the Ca2+-activated outwardly rectifying Cl- current at positive membrane potentials and carbachol (CCh)-induced Cl- currents in the whole-cell configuration at -80 mV, whereas colchicine enhanced Cl- currents. Cytochalasin D, but not colchicine, markedly inhibited CCh-induced Cl- secretion. Synergistic actions of CCh and forskolin on Cl- and amylase secretion were observed even in the presence of cytochalasin D. These results suggest that the synergistic effects of Ca2+ and cAMP signaling systems on amylase and Cl- secretion do not require actin filament integrity but that secretion by the two signals themselves does require actin filament integrity.