Fig. 7. Photomicrographs of quail brain showing negative control for (A) in situ hybridization. Brain sections were treated with RNase A prior to hybridization. (B) Brain section was not treated with AVT antiserum and served as a negative control for immunohistochemistry. Scale bars, 150 µm. PVN, paraventricular nuclei; 3V, third ventricle.