V-1 is an ankyrin repeat protein which binds to CapZ, an actin capping protein, thereby inhibiting CapZ to modulate actin dynamics. V-l also serves as a positive regulator of TH gene expression and catecholamine (CA) biosynthesis in cultured cells. Moreover, V-l stimulates high K+-induced dopamine secretion in PCI 2D cells. In the present study, we more precisely examined the functional significance of V-l in CA secretion in PCI 2D cells by using two pharmacological tools with the activity to trigger Ca2+-influx, i.e. maitotoxin (MTX), a marine toxin activating Ca2+ channels, and palytoxin (PTX), another capable of activating Na+-dependent and tetrodotoxin-insensitive voltage-dependent Ca2+ channels. Both toxins increased norepinephrine (NE) secretion in PCI 2D cells. In PCI 2D cells which stably overexpress V-l, MTX- and PTX-induced NE secretion was more remarkably stimulated than in a mock cell line. These findings suggest that V-l could regulate Ca2+-influx-dependent NE secretion possibly by modulation of actin dynamics in the adrenal chromaffin cells.
|Number of pages||5|
|Publication status||Published - 2010|
- Norepinephrine secretion
- PC12D cells
- V-1 protein
ASJC Scopus subject areas
- Pharmacology, Toxicology and Pharmaceutics(all)