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: 5.59). 03/2011; 36(8):1217-25. DOI: 10.1016/j.psyneuen.2011.02.016
Source: PubMed

ABSTRACT 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.

Download full-text


Available from: Lance J Kriegsfeld, Feb 13, 2014
  • Source
    • "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. "
    [Show abstract] [Hide abstract]
    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 · 4.51 Impact Factor
  • Source
    • "These differences in turn are associated with differences in DNA methylation: High-LG behaviour is associated with lower levels of methylation of the ERa gene, which is associated with higher levels of ERa transcription; low-LG behaviour is associated with higher levels of ERa gene methylation and lower levels of gene transcription (Cameron et al., 2008). Female offspring of low-LG mothers also exhibit increased sexual receptivity; increased levels of plasma luteinizing hormone, which regulates a number of aspects of the female menstrual cycle and accelerated puberty compared to offspring of high-LG mothers (Sakhai et al., 2011). There is evidence that human "
    [Show abstract] [Hide abstract]
    ABSTRACT: There is growing evidence that the complexity of higher organisms does not correlate with the ‘complexity’ of the genome (the human genome contains fewer protein coding genes than corn, and many genes are preserved across species). Rather, complexity is associated with the complexity of the pathways and processes whereby the cell utilises the deoxyribonucleic acid molecule, and much else, in the process of phenotype formation. These processes include the activity of the epigenome, noncoding ribonucleic acids, alternative splicing and post-translational modifications. Not accidentally, all of these pro- cesses appear to be of particular importance for the human brain, the most complex organ in nature. Because these processes can be highly environmentally reactive, they are a key to understanding behavioural plasticity and highlight the importance of the developmental process in explaining behavioural outcomes.
  • Source
    • "Across mammalian species, early life is a time of heightened susceptibility to environmental input, capable of altering the development of offspring behavior and physiology [1] [2] [3] [4]. Environmental input, particularly during periods of heightened neuronal plasticity, can increase neuron numbers, synapses, and dendritic branching, as well as inuence neuroendocrine systems such as the hypothalamic–pituitary–adrenal (HPA) or stress axis to further alter animal behavior [5] [6] [7] [8] [9] [10] [11]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Diverse environments early in mammalian life can have profound influences on the physiology and behavior of developing offspring. Environmental factors can influence offspring development directly, or, through perturbations in parental care. In the current study, we wished to determine if the influence of a single environmental variable, type of bedding material used in laboratory cages, is capable of altering physiological and behavioral outcomes in offspring. Female rats were housed in cages containing wood pulp or corncob bedding and allowed to mature. These rats, while housed on assigned bedding material, were bred and allowed to give birth. At weaning, male offspring were housed on one of the two bedding conditions and tested later in adulthood on stress-sensitive behavioral measures. Postmortem analysis of glucocorticoid receptor expression and CRH mRNA levels were also measured. Maternal care directed at the pups reared in the two different bedding conditions was also recorded. Rats reared from birth on corncob bedding exhibited decreased anxiety-like behavior, as adults, in both open field and light-dark box tasks compared to wood pulp reared animals. Animals that received similar overall levels of maternal care, regardless of bedding condition, also differed in anxiety-like behaviors as adults, indicating that the bedding condition is capable of altering phenotype independent of maternal care. Despite observed behavioral differences in adult offspring reared in different bedding conditions, no changes in glucocorticoid receptor expression at the level of the hippocampus, frontal cortex, or corticotrophin releasing hormone (CRH) mRNA expression in the hypothalamus were observed between groups. These results highlight the importance of early life housing variables in programming stress-sensitive behaviors in adult offspring.
    Physiology & Behavior 08/2013; 120. DOI:10.1016/j.physbeh.2013.08.003 · 3.03 Impact Factor
Show more