Dynasore inhibits rapid endocytosis in bovine chromaffin cells
Resource
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY,297(2),C397-C406.
Journal
AJP Cell Physiology
Journal Volume
297
Journal Issue
2
Pages
C397-C406
Date Issued
2009-08
Date
2009-08
Author(s)
Tsai, Chia-Chang
Lin, Chih-Lung
Wang, Tzu-Lun
Chou, Ai-Chuan
Chou, Min-Yi
Lee, Chia-Hsueh
Peng, I-Wei
Liao, Jia-Hong
Abstract
Vesicle recycling is vital for maintaining membrane homeostasis and neurotransmitter release. Multiple pathways for retrieving vesicles fused to the plasma membrane have been reported in neuroendocrine cells. Dynasore, a dynamin GTPase inhibitor, has been shown to specifically inhibit endocytosis and vesicle recycling in nerve terminals. To characterize its effects in modulating vesicle recycling and repetitive exocytosis, changes in the whole cell membrane capacitance of bovine chromaffin cells were recorded in the perforated-patch configuration. Constitutive endocytosis was blocked by dynasore treatment, as shown by an increase in membrane capacitance. The membrane capacitance was increased during strong depolarizations and declined within 30 s to a value lower than the prestimulus level. The amplitude, but not the time constant, of the rapid exponential decay was significantly decreased by dynasore treatment. Although the maximal increase in capacitance induced by stimulation was significantly increased by dynasore treatment, the intercepts at time 0 of the curve fitted to the decay phase were all approximately 110% of the membrane capacitance before stimulation, regardless of the dynasore concentration used. Membrane depolarization caused clathrin aggregation and F-actin continuity disruption at the cell boundary, whereas dynasore treatment induced clathrin aggregation without affecting F-actin continuity. The number of invagination pits on the surface of the plasma membrane determined using atomic force microscopy was increased and the pore was wider in dynasore-treated cells. Our data indicate that dynamin-mediated endocytosis is the main pathway responsible for rapid compensatory endocytosis.
SDGs
Type
journal article
File(s)![Thumbnail Image]()
Loading...
Name
Dynasore inhibits rapid endocytosis in bovine chromaffin cells.pdf
Size
23.5 KB
Format
Adobe PDF
Checksum
(MD5):52b598abd8ca1f9e5796bea40d34988c