Table 2.

Elevated plus maze

	Open arm entries		Closed arm entries
	Duration (in sec)	Frequency	Duration (in sec)	Frequency
Pseudopregnant WD	18  ± 2*	8.8  ± 1.4*	282.8  ± 10	6.2  ± 0.7
Pseudopregnant + MK-906	9.8  ± 3.2*	7.8  ± 2.1*	290  ± 12.6	6.9  ± 0.9
Pseudopregnant	39.8  ± 4.2	15.6  ± 3.3	259  ± 11	10.3  ± 2.4
Control	42  ± 4.5	14  ± 1.7	255.7  ± 13.5	9.3  ± 1.6

Progesterone withdrawal decreases open arm entries on the elevated plus maze. Withdrawal from elevated progesterone and 3α,5α-THP levels following ovx on day 11 of pseudopregnancy (pseudopregnant WD) resulted in a decrease in open arm time (duration) and a decrease in open arm entries (frequency) on the elevated plus maze, compared to pseudopregnant (pseudopregnant) and control animals. Blockade of 3α,5α-THP formation with MK-906 (pseudopregnant + MK-906) also reduced both open arm time and the open arm entries, in a manner similar to ovx values. (“Closed arm entries” include center square entries.) (Pseudopregnant WD, n = 30; pseudopregnant + MK-906, n = 13; pseudopregnant,n = 8; control, n = 36).

*p < 0.05 versus PP, CON.