Assessment of luteal function in the vervet monkey as a means to develop a model for obesity-related reproductive phenotype

Figures & data

Figure 1.  Determination of evidence of luteal activity (ELA) in vervet monkeys with urinary hormones, Pdg (pregnanediol glucuronide, A and C) and E1c (estrone conjugates, A, B and D). Error bars indicate standard error of the mean for composite whole cycle data. Data was centered on the day of luteal transition (A, B, and C) or the day of E1c peak (D). A) Representative hormone pattern in one ELA monkey; B) Composite whole cycle E1c for nine ELA monkeys; C) Composite whole cycle Pdg for nine ELA monkeys; D) Composite E1c for three monkeys without ELA for at least 30 days preceding a vaginal bleeding episode. Data centered on the day of E1c peak. Vaginal bleeding following E1c peak is depicted by the red arrow for three individual vervets as 1, 2, and 3, respectively.

Figure 2.  Sample DXA scan of a female vervet monkey.

Figure 3.  Examination of luteal E1c excretion (ng/mg Cr) in 9 ELA monkeys as a function of fat mass (g) determined by DXA.

Table 1. Morphometric and menstrual cycle characteristics by evidence of luteal activity.ⁱ

Determinant	Evidence of Luteal Activity (n = 9)	No Evidence of Luteal Activity (n = 3)	P Value^ii	Correlation with % Fat		Correlation with Fat Mass
				r	p	r	P
Age, years	6.82 (2.16)	8.05 (2.28)	0.41	0.37	0.24	0.45	0.14
Urinary Pdg, ug/mg Cr
Peak	0.56 (0.29)	0.35 (0.15)	0.27	0.03	0.92	0.01	0.99
Mean, luteal	0.35 (0.17)	n/a		-0.08	0.83	-0.05	0.90
Urinary E1c, ng/mg Cr
Peak	181.5 (90.3)	168.0 (95.3)	0.83	-0.23	0.47	-0.31	0.32
Mean, total cycle	90.0 (35.9)	61.5 (12.3)	0.22	-0.23	0.48	-0.29	0.35
Mean, follicular	95.4 (30.7)	n/a		-0.44	0.23	-0.46	0.21
Mean, luteal	85.7 (41.8)	n/a		-0.58	0.10	-0.61	0.08
Menstrual Cycle Parameters
Cycle length, days	29.6 (2.9)	31.3 (7.5)	0.56	-0.64	0.02	-0.53	0.08
Duration of menses, days	2.6 (0.7)	2.5 (0.8)	0.84	-0.24	0.45	-0.11	0.73
Bleeding score ^iii	1.84 (0.26)	1.64 (0.32)	0.30	0.44	0.15	0.50	0.10
Luteal length	12.7 (3.3)	n/a
Day of luteal transition	14 (1.9)	n/a
Body Weight, kg	5.0 (0.6)	4.3 (0.3)	0.09	0.72	0.01	0.77	0.003
Bone Mineral Density, g/cm^3	0.32 (0.03)	0.31 (0.03)	0.55	0.64	0.02	0.79	0.002
Fat Mass, g	893.4(309.6)	567.2 (99.2)	0.12	0.96	0.0001
Percent Fat	17.5 (4.0)	13.2 (2.6)	0.12			0.96	0.0001

¹ values presented as mean (standard deviation)

² comparison by evidence of luteal activity, t test

³ 0 (no bleeding), 1 (light), 2 (moderate), or 3 (heavy)

Figure 4.  Representative serum hormone pattern in one ELA monkey and one no ELA monkey. Vaginal bleeding is depicted by the red bars for corresponding cycle days. Removal of the corpus luteum was performed on cycle day #21 for the ELA monkey.