NMDAR1 knockout increases the number of cholinergic neurons in mouse hypothalamic cultures. Representative images are shown. A: most of the neurons in the control cultures were not stained for ChAT. B–D: ChAT-positive (dark) and ChAT-negative (light) neurons were found in AP5 + CNQX–treated (B), AP5-treated (C), and NMDAR1 knockout (D) cultures. AP5, d,l-2-amino-5-phosphonovalerate; CNQX, 6-cyano-7-nitroquinoxaline-2,3-dione; NMDAR1, N-methyl-d-aspartate receptor subunit 1.