The myoepithelial cells of these breast ducts and lobules show a strongly positive cytoplasmic staining reaction for smooth muscle myosin heavy chain.
The smooth muscle stroma of this prostate with adenomatous hyperplasia shows moderate to strong cytoplasmic reactivity. Note that the basal cells of these glands show no staining reaction, as they are not myoepithelial cells.
The cortical epithelial cells of the adrenal gland show no staining reaction for smooth muscle myosin heavy chain.
A small vessel lined by smooth muscle shows a strong granular cytoplasmic staining reaction.