Every place i've elk hunted (and moose) has moderate to high numbers of both wolves and grizzly, and my home region also has high mt. lion numbers as well.
I called in four young wolves while elk hunting two seasons ago (and no, there was no drama), but i am always aware of possible grizzly responses (so far no contact). After Bart Schleyer was killed in AK a few years back by a grizzly while cow calling moose i became really, really aware of predatory responses in grizzlies.
My scariest was when i wasn't calling, but doubled back on my tracks to find a large tom lion had been following me (his tracks in my tracks) for 300 yards while i was traversing between basins. When i'm in lion country i never call or even just sit unless my back is to a tree.