GSE174753
Effects of early life adversity on male reproductive behavior and the medial preoptic area
Early life adversity has been linked to altered reproductive development in humans, including changes in the timing of pubertal onset and sexual activity. One common form of early life adversity is having limited access to resources. This form of early life adversity can be modeled in rodents using the limited bedding and nesting model (LBN), in which rat dams and pups are placed in a low resource environment from postnatal day (PND) 2 through 9. Our laboratory has previously shown that male rats raised in LBN conditions have elevated levels of plasma estradiol compared to control males. Female rats, on the other hand, show no effect of LBN on plasma hormone levels, pubertal timing, or estrous cycle duration in adulthood. Here, we find that LBN males also show changes in adult reproductive behaviors. LBN males acquired the suite of reproductive behaviors more quickly than their control counterparts over the course of 3 weeks of testing, showing shorter latencies to mount, intromit, and ejaculate compared to controls prior to the final week of testing. We also characterized LBN-induced gene transcription changes across sex in the medial preoptic area (mPOA) which underlies reproductive behaviors. Interestingly, there was no effect of LBN on puberty onset (as measured by preputial separation) or masculinization of the sexually dimorphic nucleus of the preoptic area (SDN/POA; as measured by calbindin immunoreactivity) in males, suggesting LBN may not exert effects on hormone-dependent measures until after puberty. Overall design: 24 samples were anlayzed, including 6 male controls, 6 male experimental, 6 female controls, and 6 female experimental.