Skip to main content
Article thumbnail
Location of Repository

Activation of store-operated channels by noradrenaline via protein kinase C in rabbit portal vein myocytes

By A P Albert and W A Large

Abstract

In the present study we have investigated the role of diacylglycerol (DAG) and protein kinase C (PKC) in mediating activation of Ca2+-permeable store-operated channels (SOCs) by noradrenaline in rabbit portal vein smooth muscle cells. With cell-attached recording, bath application of noradrenaline, 1-oleoyl-acetyl-sn-glycerol (OAG) and phorbol 12,13-dibutyrate (PDBu) evoked single channel currents. The biophysical properties of these channel currents were similar to those of the channel currents activated by depletion of internal Ca2+ stores with cyclopiazonic acid (CPA). The activation of SOCs in cell-attached recording by noradrenaline, OAG, PDBu, CPA and the acetoxymethyl ester form of BAPTA (BAPTA-AM) was markedly inhibited by the PKC inhibitors chelerythrine and RÖ-31-8220. In isolated outside-out patches CPA did not evoke SOCs but noradrenaline stimulated SOC activity, which was reduced by about 90 % by PKC inhibitors. The addition of the serine/threonine phosphatase inhibitors calyculin A and microcystin also stimulated SOCs in isolated outside-out patches. It is concluded that in rabbit portal vein myocytes, noradrenaline activates SOCs via DAG and PKC, possibly by a store-independent mechanism. In addition in this cell type it appears that PKC and phosphorylation may play an important role in stimulating SOC activity in response to depletion of internal Ca2+ stores by CPA and BAPTA-AM

Topics: Original Articles
Publisher: Blackwell Science Inc
OAI identifier: oai:pubmedcentral.nih.gov:2290557
Provided by: PubMed Central
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://www.pubmedcentral.nih.g... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.