Postnatal chemical Notch inhibition results in decreased mRNA levels of Pou1f1 (Pit1), Prl, and Tshb and increased levels of Pomc. A, Experimental design for in vivo subcutaneous DAPT injection (Inj). mRNA levels of Pou1f1, Prl, and Tshb are significantly decreased and mRNA levels of Pomc are significantly increased in whole pituitaries after DAPT injection compared with those in vehicle-treated mice. B, mRNA levels of Gh and Lhb are unchanged between the two groups. *, P < .05. n = 3 to 5.