>would like to know if the meta tag "pragma" no-cache or "expires" has any effect on the Search Engine Indexing.
You appear to have answered your own question.
>I added them and my page listing dropped to nothing.
Try taking them out and see if the pages recover.
From an indexing standpoint, if the page owner has indicated that a page is going to be short-lived by including
EXPIRES and NO-CACHE, it would not make much sense to index it.
Unless you are updating pages hourly there is little chance of the visitors seeing stale pages from their private
cache, and the other caches have ways to update themselves as needed.