Big stack, big draw, do I have to lay this down?

[Rick Diesel]

Stars $11 rebuy. Hero has 40,000 and is chip leader at the table. Average is about 14,000. Blinds are 200/400 with 50 ante. Hero has A [img]/images/graemlins/heart.gif[/img]Q [img]/images/graemlins/heart.gif[/img] on the button. There are two limpers ahead. Hero calls. Both blinds come along.

The flop is 7 [img]/images/graemlins/heart.gif[/img]6 [img]/images/graemlins/heart.gif[/img]4 [img]/images/graemlins/club.gif[/img].

The BB (with about 10K) bets out for 1,200. EP (with about 13K) cold calls. MP (with about 22K) raises it 5,200 more. Your play is?