Basically, you want the sustain part of the tone increased in relation to the attack part. There are three ways to do that with amps settings/ effects: either you increase the gain of the amp, you add an overdrive effect, or you add a compression effect. The first and second will alter your tone more or less drastically, the third should be a lot less noticeable. Check the section of your amp's manual that deals with effects, and play with some of the "Booster" effects it offers, or the "Comp" effect.
Also, take a closer look at your playing technique and your guitar setup. The amp can only amplify what comes out of the guitar. Make sure that the tone rings clearly throughout your bends and that it doesn't get killed by sloppy fingering or high frets.