How do you change brake pads on a Honda Civic?

I've been changing brake pads for years but i've never come across anything like this. I took off the tire and I took the bolt off on the top of the caliper. The only problem is that the bottom bolt on the caliper is so stuck on there I can't take it off. When I go to to Turn it with the wrench it keeps turning very slowly and doesn't give me that loud screeching noise that assures you that the bolt is untighting. I am afraid of putting too much force on the bolt because I don't want to strip it. I took it to the dealership to get the previous brake pads removed (under warranty) and I have a feeling they may have tighting the bolt so tight it's striped inside of the caliper. What should I do to get the bolt out?