ChAT in adult primate ovaries. A: ChAT is detectable using immunohistochemical methods in a monkey ovary only in the GC layer (arrows) of several large antral follicles. Note that the areas between the sectioned follicles are devoid of any immunoreactive structures. Bar = 500 μm. B: A consecutive section of the one shown in A is depicted and used as a control (incubation with non-immune mouse normal serum instead of the specific antibody). The asterisk denotes a large antral follicle. Bar = 200 μm. C. Immunoreactive GCs of a large antral follicle in a human ovary. Bar = 50 μm.