The two-piece sliders on some kitchen drawers are often fitted with one piece screwed to the drawer side and its mating friend screwed to the carcass of the cupboard unit. They have to have a stop mechanism else the contents might fall on the floor.
Some sliders have a catch (usually the more expensive and annoying ones) but many just lift out - pull to the end of the run and lift the front of the drawer up and out it comes.
Sadly nobody can see your drawers so you'll have to work it out for yourself - by observation trial and error...
Good luck...
Peccavi
September 2009