QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online October 22, 2008

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JCS Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content Social Bookmarking                         What's this?

Ins(1,4,5)P₃ goes both ways

Within arterioles, endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) communicate via gap junctions at the myoendothelial junction (MEJ). This functional coordination is important for the control of blood flow, but little is known about how heterocellular communication is controlled. For instance, it is known that the transfer of the second messenger Ins(1,4,5)P₃ from VSMCs modulates Ca²⁺ stores in ECs, whereas Ins(1,4,5)P₃ that originates in ECs does not affect VSMC Ca²⁺ stores – but how is this directionality maintained? On page 3664, Brant Isakson addresses this question. Using an EC-VSMC co-culture system, the author shows that intercellular Ins(1,4,5)P₃ signalling is not affected by modulating the connexin composition of gap junctions. Notably, however, the Ins(1,4,5)P₃ receptor Ins(1,4,5)P₃-R1 is selectively localised to the EC side of the MEJ, and knocking down the expression of the receptor abolishes the response to Ins(1,4,5)P₃ in ECs. Moreover, VSMCs that are loaded with a phosphatase inhibitor respond to EC-generated Ins(1,4,5)P₃. The author concludes that Ins(1,4,5)P₃ transport at the MEJ is bidirectional but that, because of the position of the Ins(1,4,5)P₃ receptor, only ECs mount a response before Ins(1,4,5)P₃ is degraded. The MEJ might, therefore, act as a cellular signalling domain within the vasculature.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

Related articles in JCS:

Localized expression of an Ins(1,4,5)P₃ receptor at the myoendothelial junction selectively regulates heterocellular Ca²⁺ communication

Brant E. Isakson
JCS 2008 121: 3664-3673. [Abstract] [Full Text]  

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JCS Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content Social Bookmarking                         What's this?