Maternal Behavior In Rodents Research Articles

Altered responsiveness to pups in virgin female mice of the BTBR strain: Insights from pattern of c-Fos expression in brain regions involved in maternal behavior

BTBR is an inbred mouse strain that displays several behavioral alterations resembling the core symptoms of Autism Spectrum Disorder, including deficit in sociability. In the present study, we investigated whether the pup-induced maternal behavior in virgin female mice, a naturally rewarding behavior, is impaired in this strain similarly to social interaction with adult conspecifics. We firstly assessed the maternal responsiveness towards newly born pups expressed by either virgin female mice of the BTBR strain or of the normo-social B6 strain. Next, we examined in both strains the expression of c-Fos as a marker of neuronal activity in selected brain areas involved in the regulation of maternal behavior in rodents including the olfactory bulb, the medial preoptic area and the paraventricular nucleus (PVN). We also examined the effects of pup presentation on oxytocinergic neurons of the PVN, the major brain site of synthesis of oxytocin, which has a pivotal role in facilitation of maternal response and social responsiveness in general. As a final step, we assessed the c-Fos expression pattern comparing the effect of exposure to pups with that induced by exposure to another social stimulus, focusing on other areas implicated in maternal responsiveness as well as in the affective component of social behavior such as pyriform cortex and central and basolateral amygdala.Our data showed that BTBR virgin females are less responsive to presentation of pups in comparison to B6, in parallel with lower activation of brain areas implicated in the maternal and social responsiveness.

0272 Effects of Gestational Sleep Restriction on Maternal Behavior in Rodents: A Systematic Review and Meta-Analysis

Abstract Introduction Sleep restriction during pregnancy is related with postpartum depression in clinical settings. Preclinical studies have been conducted in rodent models of maternal behavior, intending to evaluate the mechanisms behind this relationship, but have raised inconsistent data so far. Our aims were to perform a preclinical meta-analysis, evaluating the actual effects or prenatal sleep restriction on maternal behavior in rodents. Methods A bibliographic search was conducted in Pubmed, Scopus, Web of Science, Psychinfo and Lilacs. Search strategy encompassed three domains: sleep restriction during pregnancy (as intervention), maternal behavior (as outcome) and experimentation animals (as population). Studies were first selected based on titles and abstracts, followed by full text analysis and data extraction. Individual effect size for each articles was calculated using standardized mean difference and meta-analysis was conducted using a DerSimonian and Laird random effects model. Results 144 articles were included in our initial data screening. Sample was reduced to six records after screening. A meta-analysis was performed, including data from two maternal behavior tests (pup retrieval test and ethogram-based analyses). A total of 115 animals were included. Meta-analysis showed that sleep restriction during pregnancy have no significant effects on maternal behavior. Conclusion Clinical studies and meta-analysis have shown that sleep restriction and disorders during pregnancy increase risk for postpartum depression. However, preclinical studies fail to corroborate these results, as sleep restriction during pregnancy does not reduce maternal behavior in rodents. The presence of negative effects in women and the maintenance of normal maternal behavior levels in rodents under comparable intervention demonstrate that other factors might mediate this relationship (among which, sociocultural factors might play a role). The maintenance of maternal behavior seems to be an adaptive behavior, assuring the suitability and survival of the litter, even in face of environmental stresses. Support AFIP, FAVC, CNPq, FAPESP

啮齿动物主动母性行为动态改变的神经机制

啮齿动物主动母性行为动态改变的神经机制

Assessing the Effects of Antipsychotics on Parenting

Context: Mental health professionals interact with substantial numbers of parents, mainly mothers, who suffer from severe mental disorders and who are treated, acutely or chronically, with antipsychotic medication. The behavior of these clients is affected by their primary illness but also by many other factors, including their drug regimen. The treating team, however, does not always recognize that a drug can profoundly impact cognition and behavior. The aim of this paper is to inform non-medical mental health workers how antipsychotic medication (AP) can influence client cognition and behavior, and thereby impact the safety of the client’s children. Indirectly, APs can also affect the immediate and longer-term behavior of the children. Evidence Acquisition: This article qualitatively reviews the very sparse literature on antipsychotic effects on cognition and behavior in populations of mentally ill mothers of young children. This narrative review includes case illustrations taken from a clinic for women with psychotic disorders. Also included are references to studies of rodent maternal behavior, as influenced by antipsychotic drugs. Results: Animal studies have shown that maternal behavior in rodents is impaired by antipsychotic drugs. In humans, drug effects such as sedation, dizziness, indicated thinking, tardive dyskinesia, increased appetite, and sleepwalking, as well as client beliefs about and attitudes toward their drugs, can affect their problem solving, decision-making, and behavior and, thus, play a critical role in child custody determinations. Behavior induced by drugs includes issues of tolerance, withdrawal, and sensitization. Importantly, there are major safety concerns related to APs. Conclusions: Listening attentively when clients speak about their drugs and understanding potential drug effects help mental health professionals increase their therapeutic efficacy and make sound decisions about clients and their children.

Bisphenol S (BPS) Alters Maternal Behavior and Brain in Mice Exposed During Pregnancy/Lactation and Their Daughters.

Estrogenic endocrine disrupting chemicals have been shown to disrupt maternal behavior in rodents. We investigated the effects of an emerging xenoestrogen, bisphenol S (BPS), on maternal behavior and brain in CD-1 mice exposed during pregnancy and lactation (F0 generation) and in female offspring exposed during gestation and perinatal development (F1 generation). We observed different effects in F0 and F1 dams for a number of components of maternal behavior, including time on the nest, time spent on nest building, latency to retrieve pups, and latency to retrieve the entire litter. We also characterized expression of estrogen receptor α in the medial preoptic area (MPOA) and quantified tyrosine hydroxylase immunoreactive cells in the ventral tegmental area, 2 brain regions critical for maternal care. BPS-treated females in the F0 generation had a statistically significant increase in estrogen receptor α expression in the caudal subregion of the central MPOA in a dose-dependent manner. In contrast, there were no statistically significant effects of BPS on the MPOA in F1 dams or the ventral tegmental area in either generation. This work demonstrates that BPS affects maternal behavior and brain with outcomes depending on generation, dose, and postpartum period. Many studies examining effects of endocrine disrupting chemicals view the mother as a means by which offspring can be exposed during critical periods of development. Here, we demonstrate that pregnancy and lactation are vulnerable periods for the mother. We also show that developmental BPS exposure alters maternal behavior later in adulthood. Both findings have potential public health implications.

Variations in maternal behavior in rats selected for infant ultrasonic vocalization in isolation

Individual differences in maternal behavior in rodents are associated with altered physiology and behavior in offspring across their lifespan and across generations. Offspring of rat dams that engage in high frequencies of high-arched-back nursing and pup-licking (High-LG) show attenuated stress responses compared to those engaging in lower frequencies (Low-LG). Selective breeding also produces widespread alterations in physiology and behavior that are stable over generations. To examine processes underlying generational and developmental influences on anxiety in an animal model, we developed two lines of rats that emit either extremely high (High-USV) or low (Low-USV) rates of 45kHz ultrasonic vocalizations in isolation at postnatal day 10. Compared to the Low-USV line, High-USV rats display increased indices of anxiety- and depression-like behavior in adulthood. The current study assessed maternal behaviors as well as oxytocin and vasopressin receptor density in High-USV and Low-USV dams to determine if selective breeding had produced differences that paralleled those found in Low- and High-LG dams. We found that Low-USV dams engage in more high-arched nursing and pup-licking than High-USV dams. Differences in oxytocin and vasopressin receptor levels were not widespread throughout the brain, with line differences in the piriform cortex and nucleus accumbens. This research illustrates the potential interplay between genetically determined (USV line) and environmental (postnatal mother–infant interactions) factors in accounting for the phenotypes associated with maternal separation induced postnatal vocalizations.

Neuronal serotonin in the regulation of maternal behavior in rodents

Maternal behavior is probably the most important pro-social behavior in female mammals, ensuring both the development and survival of her offspring. Signals driving maternal behaviors are complex and involve several brain areas, most of which are innervated by serotonin. Serotonin transmission influences maternal processes indirectly through release of maternally-relevant hormones such as prolactin, oxytocin and vasopressin, but it can also have more direct effects on survival and the growth rate of offspring, as well as on maternal care, aggression and pup killing. This article aims to examine the basics of the components of maternal behaviors in rodents and the neural systems underpinning these maternal responses with special emphasis on the role of neural serotonin in the regulation of these behaviors.

Анализ материнского поведения ручных и агрессивных серых крыс

Maternal behavior in rodents is associated with long-term programming of individual coping capacities in the offspring and includes a large number of components. This work was aimed to study maternal behavior in tame and aggressive gray rats selected for absence and enhancement of aggressiveness towards human. The study was carried out from 1 to 12 days of nursing at various time of day. It was shown that the frequency of "outside the nest" and passive nursing was higher and the frequency of maternal arched-back nursing and mother licking/grooming was lower in tame compared to aggressive dams especially at the first week of nursing. The tame dams spent less time building nest, they displayed "rest" and self-grooming more frequently. Beginning from the first week of nursing the frequency of "outside the nest" increased in the morning (09:00) and the evening and night (18:00 and 22:00) in tame dams, while the increase of activity was observed in aggressive females only in dark phase (22:00). In the third week of nursing the similar circadian changes of activity were observed in tame and aggressive dams. It is supposed that decreased anxiety in tame compared to aggressive dams could provoke the attenuation of maternal behavior.

Variations in Maternal Behavior—Oxytocin and Reward Pathways—Peripheral Measures Matter?!

Variations in Maternal Behavior—Oxytocin and Reward Pathways—Peripheral Measures Matter?!

Combined Norepinephrine/Serotonergic Reuptake Inhibition: Effects on Maternal Behavior, Aggression, and Oxytocin in the Rat

Background: Few systematic studies exist on the effects of chronic reuptake of monoamine neurotransmitter systems during pregnancy on the regulation of maternal behavior (MB), although many drugs act primarily through one or more of these systems. Previous studies examining fluoxetine and amfonelic acid treatment during gestation on subsequent MB in rodents indicated significant alterations in postpartum maternal care, aggression, and oxytocin levels. In this study, we extended our studies to include chronic gestational treatment with desipramine or amitriptyline to examine differential effects of reuptake inhibition of norepinephrine and combined noradrenergic and serotonergic systems on MB, aggression, and oxytocin system changes. Methods: Pregnant Sprague-Dawley rats were treated throughout gestation with saline or one of three doses of either desipramine, which has a high affinity for the norepinephrine monoamine transporter, or amitriptyline, an agent with high affinity for both the norepinephrine and serotonin monoamine transporters. MB and postpartum aggression were assessed on postpartum days 1 and 6 respectively. Oxytocin levels were measured in relevant brain regions on postpartum day 7. Predictions were that amitriptyline would decrease MB and increase aggression relative to desipramine, particularly at higher doses. Amygdaloidal oxytocin was expected to decrease with increased aggression. Results: Amitriptyline and desipramine differentially reduced MB, and at higher doses reduced aggressive behavior. Hippocampal oxytocin levels were lower after treatment with either drug but were not correlated with specific behavioral effects. These results, in combination with previous findings following gestational treatment with other selective neurotransmitter reuptake inhibitors, highlight the diverse effects of multiple monoamine systems thought to be involved in maternal care.

Abnormal behavioral and neurotrophic development in the younger sibling receiving less maternal care in a communal nursing paradigm in rats

Maternal behavior in rodents has been proposed to vary as a function of the external environment and, in turn, adjust offspring's stress and fear responses. Early handling (brief periods of maternal separation during the first two weeks of life) studies and analyses of spontaneously high-caring rat mothers converge to indicate that increased levels of maternal care may reduce offspring emotionality in adulthood. However, the hypothesis that environment-dependent reduction in maternal care correlates with increased offspring vulnerability to pathology has been scarcely investigated. To test this hypothesis we studied maternal care and offspring development in young, adolescent and young-adult Sprague-Dawley rats reared in a communal nursing situation, characterized by two dams delivering their offspring four days apart and communally caring for them until weaning. We show that dams of the first-born litter show increased aggression towards the pregnant female and that offspring belonging to the second-born litter receive less maternal care compared to older cage-mates. Additionally, second-born rats show increased anxiety-related behavior in a plus-maze test in adolescence and adulthood and abnormal developmental trajectories in terms of social interaction and BDNF levels in the amygdala and hippocampus compared to both the first-born litter and to animal facility reared controls. This is the first indication that adverse environments, not requiring experimenter handling, may reduce maternal care and in turn increase offspring's emotionality and modify social behavior and BDNF developmental trajectories.

P.192 Discordant outcome of perinatal transmission of hepatitis C in twin pregnancies

Maternal behavior in rodents has been proposed to vary as a function of the external environment and, in turn, adjust offspring's stress and fear responses. Early handling (brief periods of maternal separation during the first two weeks of life) studies and analyses of spontaneously high-caring rat mothers converge to indicate that increased levels of maternal care may reduce offspring emotionality in adulthood. However, the hypothesis that environment-dependent reduction in maternal care correlates with increased offspring vulnerability to pathology has been scarcely investigated. To test this hypothesis we studied maternal care and offspring development in young, adolescent and young-adult Sprague–Dawley rats reared in a communal nursing situation, characterized by two dams delivering their offspring four days apart and communally caring for them until weaning. We show that dams of the first-born litter show increased aggression towards the pregnant female and that offspring belonging to the second-born litter receive less maternal care compared to older cage-mates. Additionally, second-born rats show increased anxiety-related behavior in a plus-maze test in adolescence and adulthood and abnormal developmental trajectories in terms of social interaction and BDNF levels in the amygdala and hippocampus compared to both the first-born litter and to animal facility reared controls. This is the first indication that adverse environments, not requiring experimenter handling, may reduce maternal care and in turn increase offspring's emotionality and modify social behavior and BDNF developmental trajectories.

Olfactory regulation of maternal behavior in mammals

In mammals, olfactory cues are extensively used in many aspects of maternal care to ensure the coordination of mother–infant interactions and consequently the normal development of the offspring. Outside the period of parturition and lactation, when the young are not a behavioral priority, olfactory cues play an inhibitory role on maternal responsiveness since in most mammalian species studied so far, nonpregnant females find the odor of young aversive. On the contrary at the time of parturition, a shift in the hedonic value of infantile odors occurs so that the young now become a very potent stimulus and this sensorial processing constitutes an important part of the maternal motivational system. Moreover, infants' odors provide a basis for individual recognition by their mothers and some species (ungulates) have developed highly specialized mechanisms for processing of the infant signals. Perception of the smell of the young also regulates various aspects of maternal behavior. Dodecyl propionate, a compound released by of pup's preputial glands, has been shown to influence anogenital licking behavior, a fundamental pattern of maternal behavior in rodents. While there is no functional specificity of either the main or the accessory olfactory systems in the development of maternal behavior amongst species, it appears that only the main olfactory system is implicated when individual odor discrimination of the young is required. Neural structures, such as the main olfactory bulb, undergo profound changes when exposed to offspring odors at parturition. These changes in synaptic circuitry contribute both to maternal responsiveness to these odors, to their memorization, and to effects of long-term maternal experience.

Influence of Father and Pregnancy on Maternal Care in Red-Backed Voles

Presence of fathers and concurrent pregnancy have been shown to influence maternal behavior in rodents, but often are confounded in studies of species that mate during postpartum estrus. I examined parent-young interactions in red-backed voles ( Clethrionomys gap-peri ) to document patterns of parental care in this species and to determine whether the separate factors of presence of father and concurrent pregnancy influenced maternal behavior. Experiments were conducted in a seminatural environment with observations occurring every other day from day 1 to day 20 of life of the young. Although male and female red-backed voles always built and maintained separate nests, there was substantial variation among females in their response to fathers in the vicinity of the natal nest. Whereas some females permitted fathers in the nest soon after birth, others reacted aggressively and prevented fathers from interacting with young throughout most of the preweaning period. Such variation in behavior of females appeared responsible, at least in part, for variation among individual males in level of paternal care. Overall, females caring for young in the presence of fathers spent less time nursing and groomed their young less frequently than did females rearing young in the absence of fathers. Lower maternal care in the father present condition may reflect reduced maternal workload in the pairs in which males spent considerable time in the nest with young or disruption caused by presence of males in the pairs in which females aggressively excluded males from the natal nest. The maternal behavior of pregnant females did not differ from that of nonpregnant females.

A neuroanatomical correlate of paternal and maternal behavior in the biparental California mouse (Peromyscus californicus).

The medial preoptic area (MPOA) is important in the control of maternal behavior in rodents, and it is sexually dimorphic. This study demonstrates that the MPOA of nonparental virgin male Peromyscus californicus (n = 10) is larger than that of virgin females (n = 9) because of a significantly greater number of neurons in the MPOA of virgin males. However, this sex difference in MPOA volume disappeared when males and females became parents. Soma size increased significantly when females became mothers. These data suggest that maternal behavior may require a structural change in the MPOA, whereas paternal responsivity, which is normally inhibited in virgin males, may require a change in neuronal activity. Furthermore, these results underscore the importance of reproductive status in examination of sexually dimorphic nuclear structures.

Sexually dimorphic behaviors.

Sex differences in behavior are the result of natural and sexual selection. The dimorphic classes of behavior described here, courtship, copulatory, and parental behaviors, reflect both kinds of evolutionary selective pressures. We can further distinguish two kinds of mechanisms that produce differences in male and female behaviors. In one, both sexes can perform a behavior but one does not because of sex differences in the external stimuli or the endocrine milieu. Maternal behavior in rodents falls into this category, as do certain other reproductive behaviors. In the other, the sensory, CNS, or motor components that produce behaviors are different in males and females. Many courtship and copulatory behaviors are in this category. I have considered some cellular mechanisms that generate sex differences in behavioral effector neurons, including sensitivity to hormones, cell number, and synaptic connectivity. A common feature of many such systems is a degree of developmental arrest: sexually dimorphic, hormone-sensitive neurons or muscles are immature at stages when other cells have completed differentiation. The cellular and molecular processes whereby hormones harness the developmental programs of behavioral effector cells remain largely unknown and are the focus of active investigation.

Advances in Reproductive Physiology

Advances in Teratology , vol 2, edited by D. H. M. Woolam, 306 pp, with illus, $16, New York: Logos Press, Academic Press, Inc., 1967. These books continue annual series begun last year. Reproductive physiology and teratology represent inclusive disciplines which embrace an immense variety of subjects, and in bothAdvances in Reproductive PhysiologyandAdvances in Teratologythe editor has decided to include articles dealing with a variety of topics, rather than a central theme. Thus, volume 2 ofAdvances in Reproductive Physiologycontains material on behavior, the Physiology of Courtship and Mating and Maternal Behavior in Rodents and Lagomorphs; items on gametes and reproductive tract functions, Formation of Egg in Domestic Chicken, The Biochemical and Physiological Relationships Between Gametes and Female Reproductive Tract, The Action of Oestrogens, and The Hormonal Interplay Controlling Egg-Implantation in Rat; and two articles discussing Growth of