The St. Louis Cardinals activated closer Jason Isringhausen from the 15-day disabled list on Friday. Isringhausen strained his right abdominal muscle during a game against Milwaukee on April 26 and was placed on the DL the following day. The 32-year-old Isringhausen, who inked a two-year contract extension with a club option for 2008 earlier this year, has appeared in 10 games this season and is 0-0 with a 1.08 ERA and seven saves. He is coming off a career campaign in 2004 for the Cardinals that saw him match a club record with 47 saves. Meanwhile, the club optioned catcher Mike Mahoney to Triple-A Memphis and purchased the contract of reliever Gabe White from the Redbirds. Finally, pitcher Kevin Jarvis was outrighted to Memphis.