In addition, changes in plasma OXT and AVP primarily reflect changes in the synthesis and release of these neuropeptides. Abnormalities in other aspects of the OXT and AVP systems, such as the receptor binding and intracellular transduction mechanism as well as the downstream transmitters and modulator systems should also be considered. In mammals, they are both synthesized in the hypothalamus supraoptic and paraventricular nuclei and stored in the posterior pituitary for release .
One of the interesting findings in our study was that levels of OXT and AVP in maternal plasma showed a significant positive correlation with each other Fig. Though it remains to be established, it seemed that in the basal physiological status, the synthesis, release and metabolism of these two neuropeptides may in some way be related. One of the major concerns is whether the concentration of peripheral OXT and AVP levels parallel that in the central nervous system.
Although a strict parallelism remains to be established, several lines of evidence suggest that plasma level of OXT did at least partially reflect its central functioning  ,  ,  , . While magnocellular neurons in the supraoptic and paraventricular nuclei were known to send axons to the posterior pituitary for release of the neuropeptides into the blood, and parvocellular neurons were more or less paracrine in nature to release nonapeptides to the vicinity of the brain, these two neuronal components may work side by side.
Compared to the OXT, the situation for AVP may be a little more complicated since the peripheral level of AVP also known as the antidiuretic hormone is greatly and quickly affected by intravascular volume and plasma osmolarity . Therefore, it is critical to minimize the impact of food and water intake before sample collection. In the present study, mothers were previously informed to fast overnight and to have only moderate amount of drinking water before sample collection.
Unfortunately, nine of them reported to have had breakfast before the blood collection. Their blood samples were therefore measured but excluded from the analysis. As can be expected, their plasma AVP levels were extremely low Median 4. Results obtained from these incidental cases confirmed that the plasma AVP levels are tightly associated with food and water intake. Sex hormones are very upstream regulators that have numerous functional targets. They play important and diverse roles in the regulation of structure and function of the central nervous system .
Prenatal androgen exposure can have long-standing and permanent effects on the structure and function of the fetal central nervous system . Lower levels of OXT and higher levels of testosterone has been associated with more autistic-like traits in healthy volunteers  ,  , . In the present study, mothers of autistic children showed higher levels of testosterone, but no changes were found in estradiol levels.
Our results agree with previous studies in which higher risk for autism has been reported among children born from women with androgen-related disorders  ,  , and provide additional evidence that maternal hyperandrogenism may be a risk factor for the onset and development of autism in children. Using PCOS patients as an elective biological model, Palomba et al demonstrated that children born from hyperandrogenic women seem to have a higher risk for PDDs, due probably to an unbalanced prenatal exposure to high levels of testosterone .
It is obvious that the amniotic androgen level is not sorely determined by the maternal androgen level, but also by the androgen produced by the fetus itself. As a preliminary study there are several limitations ought to be mentioned. Results obtained in this study may not be representing the situation as those during their pregnancy.
Therefore, further studies should be performed to observe the biochemical characteristics in mothers during their pregnancy, which will be more convincing to reflect the fetal developmental environment. The geographical distribution of autistic children are more scattered coming from broad north China areas as compared to that of the normal children, since the later were recruited mainly from kindergartens of the suburb of Beijing.
These limitations should be considered when data are interpreted. Despite these limitations and the preliminary nature of this study, our results suggest that dysregulation of OXT, AVP and testosterone in the mothers should be considered as candidate elements for the understanding and the prevention of the birth of autistic children.
Browse Subject Areas? Click through the PLOS taxonomy to find articles in your field. Abstract Background Autism is a pervasive neurodevelopmental disorder,thought to be caused by a combination of genetic heritability and environmental risk factors. Methods We determined plasma levels of OXT 40 in autism vs. Introduction Autism is a pervasive neurodevelopmental disorder characterized by various degrees of impairment in language, communication and social skills, and repetitive and stereotypic patterns of behavior .
Assessment of Autistic Symptom The following two scales were used to assess autistic symptom in autistic and normal children: 1. Biochemical Analyses 1. Measurements of testosterone and estradiol concentrations. Statistics Statistical analyses were performed with Statistical Package for the Social Science version Results Group Characteristics A total of pairs of mothers and children 62 in autism, 47 in control group met the inclusion criteria and were enrolled in this study. Download: PPT.
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Figure 1. Plasma Testosterone and Estradiol Levels Statistically significant elevation in plasma testosterone levels was found in AM 0. Table 2. Figure 3.click
Discussion Autism has received more attention around the world in recent years due to its relatively high prevalence, poor prognosis and absence of effective therapies . References 1. View Article Google Scholar 2. Carter M, Scherer S Autism spectrum disorder in the genetics clinic: a review. Clin Genet — View Article Google Scholar 3.
Am J Pharmacogenomics 5: 71— View Article Google Scholar 4. Arch Gen Psychiatry — The baby virtually forces us to love it. Rather, it is just one important component of a complex neurochemical system that allows the body to adapt to highly emotional situations. The systems necessary for reciprocal social interactions involve extensive neural networks through the brain and autonomic nervous system that are dynamic and constantly changing across the life span of an individual. We also now know that the properties of oxytocin are not predetermined or fixed. These receptors change and adapt based on life experiences.
Both oxytocin and the experience of love can change over time. In spite of limitations, new knowledge of the properties of oxytocin has proven useful in explaining several enigmatic features of love. Oxytocin may help to ensure that parents and others will engage with and care for infants; develop stable, loving relationships; and seek out and receive support from others in times of need. Just as the actual stone helped linguists decipher an archaic language by comparison to a known one, animal models are helping biologists draw parallels between ancient physiology and contemporary behaviors.
Studies of socially monogamous mammals that form long-lasting social bonds, such as prairie voles, have been especially helpful to an understanding the biology of human social behavior. Of course, oxytocin does not act alone. The systems regulated by oxytocin and vasopressin are sometimes redundant. Both peptides are implicated in behaviors that require social engagement by either males or females, such as huddling over an infant Kenkel et al.
For example, it was necessary in voles to block both oxytocin and vasopressin receptors to induce a significant reduction in social engagement, either among adults or between adults and infants. Blocking only one of these two receptors did not eliminate social approach or contact. If we accept selective social bonds, parenting, and mate protection as proxies for love in humans, research in animals supports the hypothesis that oxytocin and vasopressin interact to allow the dynamic behavioral states and behaviors necessary for love.
The specific behavioral roles of oxytocin and vasopressin are especially difficult to untangle because they are components of an integrated neural network with many points of intersection. Moreover, the genes that regulate the production of oxytocin and vasopressin are located on the same chromosome, possibly allowing coordinated synthesis or release of these peptides.
Furthermore, the pathways necessary for reciprocal social behavior are constantly adapting: These peptides and the systems that they regulate are always in flux. In spite of these difficulties, some of the different functions of oxytocin and vasopressin have been identified.
Prior to mating, prairie voles are generally social, even toward strangers. This mating-induced aggression is especially obvious in males. Oxytocin, in contrast, is associated with immobility without fear. This includes relaxed physiological states and postures that permit birth, lactation, and consensual sexual behavior. In highly social species such as prairie voles Kenkel et al. However, male care of offspring also appears to rely on both oxytocin and vasopressin Kenkel et al.
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However, the stimuli from infants or the nature of the social interactions that release oxytocin and vasopressin may differ between the sexes Feldman, Studies of rodents and of lactating women suggest that oxytocin has the important capacity to modulate the behavioral and autonomic distress that typically follows separation from a mother, child, or partner, reducing defensive behaviors and thereby supporting growth and health Carter, Because the processes involved in creating social behaviors and social emotions are delicately balanced, these be may be triggered in inappropriate contexts, leading to aggression toward friends or family.
Alternatively, bonds may be formed with prospective partners who fail to provide social support or protection. The implications of sex differences in the nervous system and in the response to stressful experiences for social behavior are only slowly becoming apparent Carter et al. Both males and females produce vasopressin and oxytocin and are capable of responding to both hormones. However, in brain regions that are involved in defensive aggression, such as the extended amygdala and lateral septum, the production of vasopressin is androgen-dependent.
Thus, in the face of a threat, males may be experiencing higher central levels of vasopressin. For example, when unpaired prairie voles were exposed to an intense but brief stressor, such as a few minutes of swimming, or injection of the adrenal hormone corticosterone, the males but not females quickly formed new pair bonds. These and other experiments suggest that males and females have different coping strategies, and possibly may experience both stressful experiences, and even love, in ways that are gender-specific.
In the context of nature and evolution, sex differences in the nervous system are important. However, sex differences in brain and behavior also may help to explain gender differences in the vulnerability to mental and physical disorders Taylor, et al. Better understanding these differences will provide clues to the physiology of human mental health in both sexes.
It is possible that these changes in the genome may even be passed to the next generation. For example, infants of traumatized or highly stressed parents might be chronically exposed to vasopressin, either through their own increased production of the peptide, or through higher levels of vasopressin in maternal milk.
Vasopressin-Rat / Mouse Neurophysin Antibodies (HK 76)
Such increased exposure could sensitize the infant to defensive behaviors or create a lifelong tendency to overreact to threat. Based on research in rats, it seems that in response to adverse early experiences of chronic isolation, the genes for vasopressin receptors can become upregulated Zhang et al. Exposure to exogenous hormones in early life also may be epigenetic. For example, prairie voles treated postnatally with vasopressin especially males were later more aggressive, whereas those exposed to a vasopressin antagonist showed less aggression in adulthood.
Conversely, in voles the exposure of infants to slightly increased levels of oxytocin during development increased the tendency to show a pair bond. However, these studies also showed that a single exposure to a higher level of oxytocin in early life could disrupt the later capacity to pair bond Carter et al. There is little doubt that either early social experiences or the effects of developmental exposure to these neuropeptides holds the potential to have long-lasting effects on behavior.
Both parental care and exposure to oxytocin in early life can permanently modify hormonal systems, altering the capacity to form relationships and influence the expression of love across the life span. Thus, we can plausibly argue that love is epigenetic. We have found that social isolation reduced the expression of the gene for the oxytocin receptor, and at the same time increased the expression of genes for the vasopressin peptide. In female prairie voles, isolation also was accompanied by an increase in blood levels of oxytocin, possibly as a coping mechanism.
However, over time, isolated prairie voles of both sexes showed increases in measures of depression, anxiety, and physiological arousal, and these changes were observed even when endogenous oxytocin was elevated. Thus, even the hormonal insurance provided by endogenous oxytocin in face of the chronic stress of isolation was not sufficient to dampen the consequences of living alone. In modern societies, humans can survive, at least after childhood, with little or no human contact. Communication technology, social media, electronic parenting, and many other recent technological advances may reduce social behaviors, placing both children and adults at risk for social isolation and disorders of the autonomic nervous system, including deficits in their capacity for social engagement and love Porges, Social engagement actually helps us to cope with stress.
The same hormones and areas of the brain that increase the capacity of the body to survive stress also enable us to better adapt to an ever-changing social and physical environment. Individuals with strong emotional support and relationships are more resilient in the face of stressors than those who feel isolated or lonely. Oxytocin exerts protective and restorative effects in part through its capacity to convert undifferentiated stem cells into cardiomyocytes. Oxytocin can facilitate adult neurogenesis and tissue repair, especially after a stressful experience.
We now know that oxytocin has direct anti-inflammatory and antioxidant properties in in vitro models of atherosclerosis Szeto et al. The heart seems to rely on oxytocin as part of a normal process of protection and self-healing. Oxytocin modulates the hypothalamic—pituitary adrenal HPA axis, especially in response to disruptions in homeostasis Carter, , and coordinates demands on the immune system and energy balance.
Long-term, secure relationships provide emotional support and down-regulate reactivity of the HPA axis, whereas intense stressors, including birth, trigger activation of the HPA axis and sympathetic nervous system. The ability of oxytocin to regulate these systems probably explains the exceptional capacity of most women to cope with the challenges of childbirth and childrearing.
Of course, as in hormonal studies in voles, the effects are likely to depend on the history of the individual and the context, and to be dose-dependent. As this research is emerging, a variety of individual differences and apparent discrepancies in the effects of exogenous oxytocin are being reported.
Most of these studies do not include any information on the endogenous hormones, or on the oxytocin or vasopressin receptors, which are likely to affect the outcome of such treatments. However, it is already clear that both love and oxytocin are powerful. Of course, with power comes responsibility. Please review our Terms and Conditions of Use and check box below to share full-text version of article. Abstract The neuropeptides vasopressin AVP and oxytocin OT have been implicated in the regulation of numerous social behaviors in adult and juvenile animals.
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