Figure 4
Micro-infusion of RU486 into the AVPV reversed the inhibitory effects of progesterone on the LH surge in PMSG-primed female rats. Representative LH surge on the afternoon of day 2 (day 0, PMSG treatment) in response to intra-AVPV RU486 infusion in a progesterone treated animal (C). Intra-AVPV infusion of vehicle (artificial cerebrospinal fluid/DMSO/ethylene glycol) failed to reverse the inhibitory effect of progesterone on the LH surge (A). Representative examples showing the absence of LH surges on the afternoon of day 2 following intra-ARC vehicle control (B) or RU486 (D) after progesterone priming. (E) AUC analysis of LH level on the afternoon of day 2 after intra-AVPV or intra-ARC administration with vehicle (Veh) or RU486 in PMSG-treated animals. Results are presented as means ± SEM. *P < 0.05, Veh vs RU486; n = 6–7 per group.
