Publications by authors named "Eelke Snoeren"

This study aims to investigate the underlying neurobiological mechanisms that regulate natural reward seeking behaviors, specifically in the context of sexual behavior and sucrose self-administration. The role of CaMKIIa+ neurons in the bed nucleus of the stria terminalis (BNST) was explored using chemogenetic silencing and -stimulation. Additionally, the study examined how these effects interacted with the internal state of the animals.

View Article and Find Full Text PDF

Selective serotonin reuptake inhibitors (SSRIs) are increasingly prescribed as medication for various affective disorders during pregnancy. SSRIs cross the placenta and affect serotonergic neurotransmission in the fetus, but the neurobehavioral consequences for the offspring remain largely unclear. Recent rodent research has linked perinatal SSRI exposure to alterations in both social and non-social aspects of behavior.

View Article and Find Full Text PDF

The assessment of sexual behavior in male rats with the aim of unraveling underlying neurobiological mechanisms has in the recent decades been reduced to the annotation of mounts, intromissions and ejaculations. To provide a better understanding of the structure and patterns of copulation, it is necessary to extend and tailor the analysis to the natural organization of male rat copulation. This will lead to better formulation of hypotheses about neurobiological underpinnings of behavior.

View Article and Find Full Text PDF

Masculinization and feminization of rat sexual behavior has been supposed to occur during a short postnatal period. However, much data have made it evident that these processes may continue until adolescence. In the present study, we evaluated whether androgen treatment of females from postnatal day 20 and onwards could alter sexual motivation and behavior in a male direction.

View Article and Find Full Text PDF

Although rats are known to emit ultrasonic vocalizations (USVs), it remains unclear whether these calls serve an auditory communication purpose. For USVs to be part of communication, the vocal signals will need to be a transfer of information between two or more conspecifics, and with the possibility to induce changes in the behavior of the recipient. Therefore, the aim of our study was to investigate the role of USVs in adult rats' social and non-social investigation strategies when introduced into a large novel environment with unfamiliar conspecifics.

View Article and Find Full Text PDF

Control of protein intake is essential for numerous biological processes as several amino acids cannot be synthesized de novo, however, its neurobiological substrates are still poorly understood. In the present study, we combined fiber photometry with nutrient-conditioned flavor in a rat model of protein appetite to record neuronal activity in the VTA, a central brain region for the control of food-related processes. In adult male rats, protein restriction increased preference for casein (protein) over maltodextrin (carbohydrate).

View Article and Find Full Text PDF

The medial amygdala (MeA) is a sexually dimorphic brain region that integrates sensory information and hormonal signaling, and is involved in the regulation of social behaviors. Lesion studies have shown a role for the MeA in copulation, most prominently in the promotion of ejaculation. The role of the MeA in sexual motivation, but also in temporal patterning of copulation, has not been extensively studied in rats.

View Article and Find Full Text PDF

Gonadal hormones affect neuronal morphology to ultimately regulate behaviour. In female rats, oestradiol mediates spine plasticity in hypothalamic and limbic brain structures, contributing to long-lasting effects on motivated behaviour. Parallel effects of androgens in male rats have not been extensively studied.

View Article and Find Full Text PDF

Obesity is a major health risk, with junk food consumption playing a central role in weight gain, because of its high palatability and high-energy nutrients. The Cafeteria (CAF) diet model for animal experiments consists of the same tasty but unhealthy food products that people eat (e.g.

View Article and Find Full Text PDF

Serotonin plays an important role in adult female sexual behavior, however little is known about the influence of serotonin during early development on sexual functioning in adulthood. During early development, serotonin acts as neurotrophic factor, while it functions as a modulatory neurotransmitter in adulthood. The occurrence of serotonin release, could thus have different effects on behavioral outcomes, depending on the developmental period in which serotonin is released.

View Article and Find Full Text PDF

SSRIs are commonly used to treat pregnant women with depression. However, SSRIs can cross the placenta and affect the development of the fetus. The effects of perinatal SSRI exposure, and especially the effects on social behavior, are still incompletely documented.

View Article and Find Full Text PDF

The use of selective serotonin reuptake inhibitors (SSRI) during pregnancy has increased tremendously, but the consequences for the offspring remain largely unclear. Several studies have described potential effects of perinatal SSRI-exposure on neurobehavioral outcomes using simplified rodent test set-ups, however these set-ups only assess a small fraction of the behavior. For translational purposes it is important to take the environmental influences into account which children are exposed to in real life.

View Article and Find Full Text PDF
Female Reproductive Behavior.

Curr Top Behav Neurosci

January 2020

Reproductive behavior is the behavior related to the production of offspring and includes all aspects from the establishment of mating systems, courtship, sexual behavior, and parturition to the care of young. In this chapter, I outline the hormonal regulation of the estrous cycle, followed by a description of the neural regulation of female sexual behavior. Ovarian hormones play an important role in the induction of ovulation and behavioral estrus, in which they interact closely with several neurotransmitters and neuropeptides to induce sexual behavior.

View Article and Find Full Text PDF

In the field of behavioral neuroscience, it is essential to use the appropriate animal models for the topic of investigation. Using the wrong model can result in false interpretation of the results. In this review we will discuss the animal models used to study sexual behavior, with a focus on rats.

View Article and Find Full Text PDF

Female mate choice is often investigated in terms of reproductive success in order to understand how male characteristics contribute to sexual attractiveness. Previous studies have found that females rats prefer mating with their first encounter rather than males visited subsequently, suggesting that the rewarding value of this first encounter is enough to reinforce mating with the first partner. Using a multiple chambers paradigm, we allowed female rats to copulate freely with three males placed each in a different chamber.

View Article and Find Full Text PDF

Intrasexual competition is an important element of natural selection in which the most attractive conspecific has a considerable reproductive advantage over the others. The conspecifics that are approached first often become the preferred mate partners, and could thus from a biological perspective have a reproductive advantage. This underlines the importance of the initial approach and raises the question of what induces this approach, or what makes a conspecific attractive.

View Article and Find Full Text PDF

Both male and female rats produce vocalizations in the presence of a potential sexual partner. In this study, we evaluated the role of vocalizations in sociosexual behaviors in an ecologically valid procedure. Three males and 4 females were housed in a seminatural environment.

View Article and Find Full Text PDF

Both male and female rats produce 50 kHz ultrasonic vocalizations (USVs) in the presence of a sexual partner and during copulation. Previous studies showed that USVs have no incentive value for rats. In this study, we evaluated the role of USVs in behavior during copulation.

View Article and Find Full Text PDF

Three different phases can be distinguished in rats' sexual cycle, the introductory (precopulatory), the copulatory and the executive (ejaculatory) phases. In this review, a new analysis of existing pharmacological data is made, both in male and female rats, in which the different aspects of sexual behavior are taken into account. An effort is made to distinguish pharmacological effects on sexual behavior from a possible physiological role of noradrenaline.

View Article and Find Full Text PDF

Intrasexual competition for access to a female mate is believed to be unusual in wild male rats, which suggests that female choosiness could be more important. It has been shown that females spend more time with one male than with others when tested in a multiple partner paradigm. The male of first entry is visited most.

View Article and Find Full Text PDF

Intrasexual competition for access to a female mate is believed to be unusual in wild male rats, which suggests that female choosiness could be important. Even if competition is unusual, males still have to inevitably approach one partner first for copulation. In females, it has been shown that females spend longer time with one male compared to the others when tested in a multiple partner paradigm.

View Article and Find Full Text PDF

This review focuses on the role of serotonin and especially 5-HT₁A receptors in female rat sexual behavior. In addition, the differences and/or similarities with male rats are discussed. Overall, in both males and females 5-HT₁A receptors do not appear to be involved in sexual behavior under normal circumstances, but become very important under conditions of elevated serotonin levels.

View Article and Find Full Text PDF

Serotonin plays an important role in male sexual behavior. Many studies have been performed on the pivotal role of 5-HT₁A receptors in sexual behavior. Overall, 5-HT₁A receptors do not appear to be involved under normal circumstances, but become very important under conditions of elevated serotonin levels in sexual behavior.

View Article and Find Full Text PDF

Rats emit ultrasonic vocalizations (USVs) of 22 kHz and 50 kHz before, during, and after copulation. The 50-kHz vocalizations can be subdivided into flat and frequency-modulated (FM) trill calls. In this study, the role of 50-kHz USVs in sexual incentive motivation in female rats was examined.

View Article and Find Full Text PDF