The team announced the move Saturday on Twitter ahead of Sunday night's home preseason game against the Arizona Cardinals.
A seventh-round draft pick out of Western Kentucky in 2014, Dowling played in seven games with no starts last season as a rookie. He made four tackles.
Dowling had his first career interception - in a preseason game - when he picked off a pass by Shaun Hill in a 20-12 loss at Minnesota last Saturday.
AP NFL website: www.pro32.ap.org and www.twitter.com/AP-NFL