Fig. 5.

Effects of POA RU486 microimplants. Left panels depict representative episodic LH secretion in OVX+E (top panels) and OVX (bottom panels) ewes receiving empty (Cont) or RU486-containing (RU486) microimplants in the POA. LH pulse patterns before (d 0) and during (d 2) treatment with one (OVX+E ewes) or two (OVX ewes) vaginal progesterone implants are shown. Solid circles depict peaks of LH pulses. Right panels present corresponding changes in LH pulse frequency (FREQ) and amplitude (AMPL) when ewes received empty (C) or RU486-containing (R) microimplants. Open bars depict values before and solid/shaded bars values during vaginal progesterone treatment. *, P < 0.05 vs. values before progesterone treatment.