Structured Breeding Groups for the Transmission of Spontaneous Hypertension in African Green Monkeys

Abstract

The African Green Monkey (AGM; Chlorocebus aethiops sabaeus) is a nonhuman primate native to the Caribbean island nation of Saint Kitts and Nevis with genetic ancestry in West Africa. We have shown that the AGM develops spontaneous hypertension (HTN) with renal glomerular pathologies and left ventricular hypertrophy. The AGM is also a translational animal model of hypertensive pregnancy disorders and the study of APOL1 genetic variation in HTN and end‐stage renal disease. Our St. Kitts colony of AGMs consists of over 230 wild‐caught animals. This study assesses the selective breeding of normotensive and spontaneously hypertensive animals and strategies for success in breeding paradigms for the potential transmission of HTN. Over the course of 3 years, the breeding groups have produced more than 80 purpose‐bred offspring. We tested the hypothesis that larger breeding groups would lead to greater reproductive success in both percent gravid females and number of live births for socially complex AGM groups. Breeding was established with one male and either 15–25 (large group) or 2–9 (small group) females. We assessed pregnancies and live births over one annual breeding season (November – March). Systolic blood pressure (SBP) and heart rates (HR) were measured via doppler stethoscope and forearm plethysmography. Breeding groups had phenotypes of hypertensive (HT; systolic blood pressure > 140 mmHg) or normotensive (NT; systolic blood pressure < 120 mmHg) male and female adults ages 5–15 years. The percentage of pregnant females for small breeding groups (70.5 ± 38.2%) was similar to that of females for large breeding groups (68.7 ± 21.6%, p>0.05). The average number of annual births for small breeding groups (2.8 ± 2.6 births) was fewer than that for large breeding groups (13.2 ± 10.6 births, p<0.05). Furthermore, when a new male was introduced to a breeding group, the percentage of gravid females was unchanged (p > 0.05). Offspring from breeding groups have been phenotyped for blood pressure and heart rate at 1 and 2 years of age (juveniles before sexual maturity). All juveniles were derived either from a NT mother and HT father (NT x HT) or two HT parents (HT x HT). SBP of NT x HT offspring did not change with age (1.2 years = 106.9 ± 3.4 mmHg, n = 19 vs 2.0 years 103.8 ± 6.8 mmHg, n = 4; p > 0.05). SBP of HT x HT offspring also remained unchanged with age (1.2 years 114.6 ± 7.2 mmHg, n = 5 vs 2.2 years 111.0 ± 9.6 mmHg, n = 3; p > 0.05). HR decreased with age in both groups (NT x HT: 1.2 years 182.5 ± 3.7 bpm, 2.0 years 165.5 ± 7.5 bpm; HT x HT: 1.2 years 188.0 ± 8.0 bpm, 2.2 years 159.0 ± 10.5 bpm; p<0.05). Offspring from HT x HT parents tended to have greater blood pressures than that of NT x HT parents. In conclusion, these data suggest that breeding group size does not affect the rate of successful mating and progeny production in AGMs. With limited space, smaller breeding groups are shown to be effective, but larger breeding groups are useful when space is not a factor. Juvenile age between 1 and 2 years does not affect changes in SBP regardless of maternal parent blood pressure phenotype when paternal phenotype is HT. Future studies will further assess the effect of both NT x NT and HT x HT parental phenotype, including genetic assessment on the development of adolescent HTN.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.