The simple answer to this is ‘No’.
PR means Public Relations, not Press Release. Let’s repeat that in different words. PR is NOT a short-form for Press Release.
Terming a Press Release as “PR” is actually a confusion, caused mostly by paid media / paid news folks from the last two years or so. Some of them say they do “PR”. But on probing, one finds out that what they mean by PR is just a Press Release, and not Public Relations or media relations.
Please understand that a Press Release is just one news article. Whereas the profession of Public Relations (PR) encompasses a host of activities including PR planning, vision, PR strategy, contacts and connections with news editors and journalists, content creation and brand placements in media.