JP, 30, who made his Scotland debut on the summer tour of New Zealand seven years ago, said: "Pro rugby has been my whole life for the past ten years or so and is a difficult thing to let go of. I've had some fantastic times with Glasgow, and with Scotland, but I have a gut feeling that now is the right time to move on to something new. I'd like to thank everybody for the support that I've been given throughout my career, especially the fans here in Glasgow, who have always been great to me."
Scotland coach Frank Hadden said: "I remember Bill McLaren coming to watch the Caledonian Reds training at Perth in '97 and he asked who the young fellow was. I told him it was Jon Petrie and he should remember the name because he was going to play for Scotland. This is not something I would normally do, which is why I remember it so clearly, but it was obvious to everyone that he was going to make a big impact.
"When I took over as Scotland coach, Jonny was my first choice as Captain and he did a great job, leading the team to a first ever win over the Barbarians at Pittodrie and only our second ever win in Romania. Latterly he has been dogged by injury but his excellent communication and leadership skills will stand him in good stead whatever career path he chooses."
Glasgow Warriors head coach Sean Lineen added: "JP is a very popular member of the squad here at Glasgow and we're sorry to see him go but respect and understand his decision. His knowledge of the game and leadership on and off the field with the club has been invaluable to us all. He has worked so hard for the Warriors throughout his time with the side and is a firm favourite not only with the other players but also with the supporters and staff. We wish him all the very best in his future career."
His retiral from the sport will see him enter the business world as he takes up a training-related post with utility company Scottish and Southern Energy in Perth, for whom he has also been a rugby ambassador since the company became involved in sponsoring the domestic competitions in Scotland earlier this season.
He said: "I have worked very hard to get to the top in rugby and am looking forward to applying the same determination to this opportunity that SSE has given me. It's going to be a very different environment for me, but is something about which I'm tremendously excited."