Figure 6.

Expression of pituitary adenylate cyclase-activating polypeptide (PACAP; A), PACAP receptor (PAC1; B), and GnRHR (C) in rat pituitary cells. The cells were first primed with 1 nmol/L E₂ for 24 hours, then with constant E₂ priming treated with 100 nmol/L progesterone (P4) for 6 or 24 hours, and 100 nmol/L gonadotropin-releasing hormone (GnRH) analog (or equal volume of H₂O as control) was added at 6 hours before sample collection. The samples were processed and measured as described in Figure 1. Bars represent the mean ± standard error of the mean of each group (n ≥ 3). Bars at the same time point with different letters vary significantly (P < .05).