sp_msreplcheck_publish is a sp that checks if you have sufficient rights to run a statement to alter a published table (transactional replication).
Trying to alter a published table without elevated rights fires trigger
tr_MStran_altertable that calls
sp_MStran_ddlrepl that execute
sp_msreplcheck_publish. It returns correctly :
Only members of the sysadmin fixed server role or db_owner fixed database role can perform this operation.
The mystery for me is that I cannot find this sp in published database or in master. Is it generated on demand?