Figure 2

Quantitation of Nodal, Lefty and Cripto mRNA expression patterns across the menstrual cycle by RT-PCR (normalized for β-actin mRNA expression). Histograms illustrating fluctuations in mRNA expression (mean values ± SEM) for Nodal, Lefty and Cripto across the menstrual cycle (Mens = menstrual phase, EP = early proliferative, LP = late proliferative, ES = early secretory, MS = mid secretory, LS = late secretory; n = 4 for each stage). Significantly elevated expression of Nodal mRNA was detected in the early secretory phase compared with the menstrual or mid/late secretory phases, while Lefty and Cripto mRNAs were significantly elevated in the late secretory phase only. Different letters indicate significant differences, P < 0.05.