Well getting something indexed has all the same principle - you can either build links to the press release, or submit it to an instant link indexing service, and either way, it will get that press release indexed accordingly, if the content is good or can contribute to the reader.
Submitting it to an instant link indexing service is very quick, but it does not last.
Building links to the press release may take a little time, but the effect would stick, and link juice may even flow to your site at the end of the process as well.