Endnote does not update bibliography....HELP!

I am writing article for publication.The journal requires journal tittles in bibliography to be abbreviated.  So I abbreviated some of journal names in endnote library expecting the software to update the bibliography. But nothing happened! Please help me to solve this problem.

Thank u. 

FUI, I am using Endnote X2.1 with Word2008 (Mac)

See the links in this previous thread for the Endnote mechanisms to handle Journal Abbreviations.