Basal and GnRH-regulated rat pituitary Gnrhr transcriptions are age and sex dependent. A and B, Time-course studies of 10 nM GnRH-induced Gnrhr expression in embryonal pituitaries (E21), neonatal (PN2) and infant to adult pituitary cells derived from 7 to 20 animals per age group were done 48 h after dispersion. The age of animals in panel B is indicated on the top of gray panels. Adult female groups were composed of animals in different stages of estrous cycle. C-E, The relationship between basal and regulated Gnrhr expression in males (closed circles), females (open circles). Data are derived from Fig. 7B; the 0 time points were used for basal (C) and the peak responses were used as values for GnRH-stimulated gene expression (D). Asterisks indicate significant differences between pairs, determined by ANOVA. E, Correlation of basal and regulated rat pituitary Gnrhr expression. R, Coefficient of correlation.