Maternal programming of sexual attractivity in female Long Evans rats

Department of Psychology, University of California at Berkeley, Berkeley, CA 94720, USA.
Psychoneuroendocrinology (Impact Factor: 4.94). 03/2011; 36(8):1217-25. DOI: 10.1016/j.psyneuen.2011.02.016
Source: PubMed


In mammals, maternal care influences the developing offspring across multiple domains. In Long Evans rats, for example, the quality of maternal care received as a pup influences later cognitive function, neuroendocrine responses to stress and behavioral measures of emotionality. Data from humans, non-human primates, and rodents also suggest that early life events may similarly perturb measures of sexual reproduction, with possible consequences for reproductive fitness. The current study examined whether or not male conspecifics differentially prefer females, as adult mating partners, that were reared under varying maternal conditions (assessed via the quantity of licking and grooming received; LG). Additionally, the impact of maternal care on adult female sexual motivation and behavior were quantified to determine if these behavioral characteristics are associated with any preference observed. In a mate preference task, male rats chose, almost exclusively, to mount, copulate and ejaculate with female rats reared under Low LG conditions. Under non-paced mating conditions, female Low LG rats display significantly more paracopulatory and copulatory behaviors compared to High LG rats. Due to its critical role in female paracopulatory behavior, progesterone receptor immunoreactivity (PR-ir) in the ventromedial nucleus of the hypothalamus (VMH) was also assessed in both groups of female rats. Estradiol induced PR-ir in the VMH was significantly higher in Low LG relative to High LG rats. Together, these data suggests that early life parental care may developmentally program aspects of behavior and physiology that subsequently influence sexual attractivity and behavior in adult females.

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Available from: Lance J Kriegsfeld, Feb 13, 2014
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    • "s , neu - ronal survival , HPA functioning and stress reactivity , sociality and reproductive behavior ( Bredy , Grant , Champagne , & Meaney , 2003 ; Cameron et al . , 2008 ; Champagne et al . , 2008 ; Engert , Joober , Meaney , Hell - hammer , & Pruessner , 2009 ; Fish et al . , 2004 ; Francis , Champagne , & Meaney , 2000 ; Liu et al . , 2000 ; Sakhai et al . , 2011 ; Starr - Phillips & Beery , 2014 ; Zhang et al . , 2005 ) . In humans , a correlation between early - life experiences and cognitive function also suggests a putative role for early - experiences in PFC development ."
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    ABSTRACT: Stress influences a wide variety of outcomes including cognitive processing. In the rat, early life maternal care can influence developing offspring to affect both stress reactivity and cognitive processes in adulthood. The current study assessed if variations in early life maternal care can influence cognitive performance on a task, the ability to switch cognitive sets, dependent on the medial prefrontal cortex. Early in life, offspring was reared under High or Low maternal Licking conditions. As adults, they were trained daily and then tested on an attentional set-shifting task (ASST), which targets cognitive flexibility in rodents. Stress-sensitive behavioral and neural markers were assayed before and after the ASST. High and Low Licking offspring performed equally well on the ASST despite initial, but not later, differences in stress axis functioning. These results suggest that early life maternal care does not impact the accuracy of attentional set-shifting in rats. These findings may be of particular importance for those interested in the relationship between early life experience and adult cognitive function. © 2015 Wiley Periodicals, Inc. Dev Psychobiol. © 2015 Wiley Periodicals, Inc.
    Developmental Psychobiology 08/2015; DOI:10.1002/dev.21343 · 3.31 Impact Factor
    • "Terminal measures of reproductive traits including uterine and testicular mass both showed trends towards higher mass in HL versus LL rats. Prior studies have shown earlier onset of fertility, increased sexual attractivity, and more proceptive behaviors in female LL offspring (Cameron et al., 2008a,2008b; Sakhai et al., 2011), which appears "
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    ABSTRACT: Since the first report of maternal care effects on DNA methylation in rats, epigenetic modifications of the genome in response to life experience have become the subject of intense focus across many disciplines. Oxytocin receptor expression varies in response to early experience, and both oxytocin signaling and methylation status of the oxytocin receptor gene (Oxtr) in blood have been related to disordered social behavior. It is unknown whether Oxtr methylation varies in response to early life experience, and whether currently employed peripheral measures of Oxtr methylation reflect variation in the brain. We examined the effects of early life rearing experience via natural variation in maternal licking and grooming during the first week of life on behavior, physiology, gene expression, and epigenetic regulation of Oxtr across blood and brain tissues (mononucleocytes, hippocampus, striatum, and hypothalamus). Rats reared by "high" licking-grooming (HL) and "low" licking-grooming (LL) rat dams exhibited differences across study outcomes: LL offspring were more active in behavioral arenas, exhibited lower body mass in adulthood, and showed reduced corticosterone responsivity to a stressor. Oxtr methylation was significantly lower at multiple CpGs in the blood of LL versus HL rats, but no differences were found in the brain. Across groups, Oxtr transcript levels in the hypothalamus were associated with reduced corticosterone secretion in response to stress, congruent with the role of oxytocin signaling in this region. Methylation of specific CpGs at a high or low level was consistent across tissues, especially within the brain. However, individual variation in methylation relative to these global patterns was not consistent across tissues. These results suggest that blood Oxtr methylation may reflect early experience of maternal care, and that Oxtr methylation across tissues is highly concordant for specific CpGs, but that inferences across tissues are not supported for individual variation in Oxtr methylation. Copyright © 2015. Published by Elsevier Inc.
    Hormones and Behavior 06/2015; DOI:10.1016/j.yhbeh.2015.05.022 · 4.63 Impact Factor
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    • "First, the combination of METH and EB + P increased the number of PR immunoreactive cells to levels greater than either one alone, suggesting that enhanced PR signaling in the MePD may underlie the facilitation of proceptive behaviors. Indeed, a positive correlation has been reported between PR expression in the VMN and the degree of proceptive behaviors ; female rats that display more proceptive behaviors have a higher induction of PR in the VMN following estradiol-treatment (Sakhai et al., 2011). Second, administration of RU486 into the MePD prevented the enhancement of female sexual behavior by METH without affecting basal proceptive or receptive behaviors, indicating that METH interacts with ovarian steroids at the level of the PR. "
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    ABSTRACT: Methamphetamine (METH) is a psychomotor stimulant strongly associated with increases in sexual drive and impulsive sexual behaviors that often lead to unsafe sexual practices. In women METH users, such practices have been associated with increases in unplanned pregnancies and sexually transmitted diseases. Despite this significant heath concern, the neural mechanisms underlying this drug-sex association are not known. We previously established a rodent model of METH-facilitated female sexual behavior in which estradiol and progesterone interact with METH to increase motivational components of female behavior and neuronal activation in the posterodorsal medial amygdala (MePD) (Holder et al., 2010; Holder and Mong, 2010). The current study more directly examines the mechanisms underlying the drug-sex interaction. Here, we hypothesize that METH-induced increases in MePD dopamine signaling bridge the METH-hormone interaction. In support of this hypothesis, we found that excitotoxic lesions targeted to the MePD attenuated the METH-induced increases in proceptive behavior. Furthermore, infusion of a D1 agonist into the MePD increased proceptive behavior, while infusion of a D1 antagonist blocked the ability of METH to increase proceptive behaviors. Additionally, we found that METH-treatment increased progesterone receptor (PR) immunoreactivity in the MePD, suggesting an interaction between dopamine and progesterone signaling. Indeed, infusions of the PR antagonist, RU486, prevented METH-induced increases in sexual behavior. Thus, taken together, the current findings suggest that dopamine in the MePD modulates enhanced sexual motivation via an amplification of progesterone signaling and contributes to a better understanding of the neurobiology of drug-enhanced sexual behaviors.
    Hormones and Behavior 11/2014; 67. DOI:10.1016/j.yhbeh.2014.10.004 · 4.63 Impact Factor
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