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Purpose: Oxytocin and arginine vasopressin are associated with different aspects of the stress response. As stress is regarded as a risk factor for vocal symptoms, we wanted to explore the association between the oxytocin receptor gene (OXTR) and arginine vasopressin 1A receptor gene (AVPR1A) single-nucleotide polymorphisms (SNPs) and vocal symptoms. We also wanted to explore whether such effects might be mediated by cortisol because oxytocin and vasopressin are associated with cortisol levels. Method: A population-based sample (N = 657) of Finnish twins (born 1961-1989) completed a web questionnaire on the occurrence of vocal symptoms. A total of 170 participants submitted saliva samples for hormone analysis. A total of 20 OXTR and AVPR1A SNPs were analyzed. Results: Three OXTR polymorphisms (rs2270465, rs2268493, rs7632287) and 2 AVPR1A polymorphisms (rs1587097, rs1042615) showed nominal effects (p < .05) on vocal symptoms, of which 1 (rs1587097) remained significant after correcting for multiple testing (p = .003). We found potential mediation of the effect of the OXTR rs2268493 polymorphism on vocal symptoms through levels of cortisol. Conclusions: The associations between variants of OXTR and AVPR1A and vocal symptoms indicate that oxytocin and vasopressin might influence vocal symptoms. The effect of oxytocin seems to be partly mediated through cortisol actions., Stress has been indicated as a risk factor for vocal symptoms (Dietrich, Verdolini Abbott, GartnerSchmidt, & Rosen, 2008; Giddens, Barron, ByrdCraven, Clark, & Winter, 2013; Rantala, Hakala, Holmqvist, & Sala, [...]

Oxytocin is important for social interactions and maternal behaviour. However, little is known about when, where and how oxytocin modulates neural circuits to improve social cognition. Here we show how oxytocin enables pup retrieval behaviour in female mice by enhancing auditory cortical pup call responses. Retrieval behaviour required the left but not right auditory cortex, was accelerated by oxytocin in the left auditory cortex, and oxytocin receptors were preferentially expressed in the left auditory cortex. Neural responses to pup calls were lateralized, with co-tuned and temporally precise excitatory and inhibitory responses in the left cortex of maternal but not pup-naive adults. Finally, pairing calls with oxytocin enhanced responses by balancing the magnitude and timing of inhibition with excitation. Our results describe fundamental synaptic mechanisms by which oxytocin increases the salience of acoustic social stimuli. Furthermore, oxytocin-induced plasticity provides a biological basis for lateralization of auditory cortical processing., The neuropeptide oxytocin controls social behaviours such as pair bond formation, mating and parenting (1-14). Oxytocin is synthesized in the paraventricular nucleus (PVN) and supraoptic nucleus of the hypothalamus, and [...]

Background: Oxytocin (OXT) plays a prominent role in social cognition and may have clinical applications for disorders such as autism, schizophrenia and social anxiety. The neural basis of its mechanism of action remains unclear. Methods: We conducted a systematic literature review of placebo-controlled imaging studies using OXT as a pharmacological manipulator of brain activity. Results: We identified a total of 21 studies for inclusion in our review, and after applying additional selection criteria, 11 of them were included in our fMRI voxel-based meta-analysis. The results demonstrate consistent alterations in activation of brain regions, including the temporal lobes and insula, during the processing of social stimuli, with some variation dependent on sex and task. The meta-analysis revealed significant left insular hyperactivation after OXT administration, suggesting a potential modulation of neural circuits underlying emotional processing. Limitations: This quantitative review included only a limited number of studies, thus the conclusions of our analysis should be interpreted cautiously. This limited sample size precluded a more detailed exploration of potential confounding factors, such as sex or other demographic factors, that may have affected our meta-analysis. Conclusion: Oxytocin has a wide range of effects over neural activity in response to social and emotional processing, which is further modulated by sex and task specificity. The magnitude of this neural activation is largest in the temporal lobes, and a meta-analysis across all tasks and both sexes showed that the left insula demonstrated the most robust activation to OXT administration., Introduction The role of oxytocin (OXT) in influencing social behaviour has been well established in animal research, (1,2) but over the past decade it has been increasingly shown to be [...]

Byline: Maria. Cecilia, Reeta. Vijayaselvi, Ramandeep. Bansal, Latha. Lakshmi, Ruby. JoseOBJECTIVES: Currently, recommended high-dose oxytocin regimen for the prevention of postpartum hemorrhage (PPH) following cesarean delivery (CD) is associated with [...]

The evolutionarily highly conserved neuropeptide oxytocin is a key mediator of social and emotional behavior in mammals, including humans. A common variant (rs53576) in the oxytocin receptor gene (OXTR) has been implicated in social-behavioral phenotypes, such as maternal sensitivity and empathy, and with neuropsychiatric disorders associated with social impairment, but the intermediate neural mechanisms are unknown. Here, we used multimodal neuroimaging in a large sample of healthy human subjects to identify structural and functional alterations in OXTR risk allele carriers and their link to temperament. Activation and interregional coupling of the amygdala during the processing of emotionally salient social cues was significantly affected by genotype. In addition, evidence for structural alterations in key oxytocinergic regions emerged, particularly in the hypothalamus. These neural characteristics predicted lower levels of reward dependence, specifically in male risk allele carriers. Our findings identify sex-dependent mechanisms impacting the structure and function of hypothalamic-limbic circuits that are of potential clinical and translational significance. imaging genetics | neuroimaging | social behavior | prosocial neuropeptides | autism doi/ 10.1073/pnas.1003296107

Social adaptation requires specific cognitive and emotional competences. Individuals with high-functioning autism or with Asperger syndrome cannot understand or engage in social situations despite preserved intellectual abilities. Recently, it has been suggested that oxytocin, a hormone known to promote mother-infant bonds, may be implicated in the social deficit of autism. We investigated the behavioral effects of oxytocin in 13 subjects with autism. In a simulated ball game where participants interacted with fictitious partners, we found that after oxytocin inhalation, patients exhibited stronger interactions with the most socially cooperative partner and reported enhanced feelings of trust and preference. Also, during free viewing of pictures of faces, oxytocin selectively increased patients' gazing time on the socially informative region of the face, namely the eyes. Thus, under oxytocin, patients respond more strongly to others and exhibit more appropriate social behavior and affect, suggesting a therapeutic potential of oxytocin through its action on a core dimension of autism. cognition | neurodevelopmental disorder | recovery | Syntocinon doi/10.1073/pnas.0910249107

Am J Physiol Regul Integr Comp Physiol 298: R157-R165, 2010. First published November 4, 2009; doi: 10.1152/ajpregu.00328.2009.--Accumulation of continuous life stress (chronic stress) often causes gastric symptoms. The development of gastric symptoms may depend on how humans adapt to the stressful events in their daily lives. Although acute stress delays gastric emptying and alters upper gastrointestinal motility in rodents, the effects of chronic stress on gastric motility and its adaptation mechanism remains unclear. Central oxytocin has been shown to have antistress effects. We studied whether central oxytocin is involved in mediating the adaptation mechanism following chronic repeated stress. Mice were loaded with acute and chronic stress (repeated stress for five consecutive days), and solid gastric emptying and postprandial gastric motility were compared between acute and chronic repeated stress. Expression of oxytocin and CRF mRNA in the hypothalamus was studied following acute and chronic repeated stress. Delayed gastric emptying during acute stress (43.1 [+ or -] 7.8%; n = 6, P < 0.05) was completely restored to normal levels (72.1 [+ or -] 2.4%; n = 6) following chronic repeated stress. Impaired gastric motility induced by acute stress was also restored following chronic repeated stress. Intracerebroventricular injection of oxytocin (0.1 and 0.5 [micro]g) restored the impaired gastric emptying and motility induced by acute stress. The restored gastric emptying and motility following chronic repeated stress were antagonized by intracerehroventricular injection of oxytocin antagonists. Oxytocin mRNA expression in the supraoptic nucleus (SON) and paraventricular nucleus (PVN) of the hypothalamus was significantly increased following chronic repeated stress. In contrast, increased CRF mRNA expression in the SON and PVN in response to acute stress was significantly reduced following chronic repeated stress. Our study suggests the novel finding that the upregulation of central oxytocin expression is involved in mediating the adaptation mechanism following chronic repeated stress in mice. key words; acute stress; chronic stress; corticotropin-releasing factor; hypothalamus-pituitary-adrenal axis

Among the cardiovascular pathologies, ischemic heart disease is a serious medical problem that can result in cardiac injury and (or) heart failure. The aim of the present study was to test the hypothesis that neuropeptide oxytocin induces cardioprotective effects on ischemia-reperfusion-induced myocardial damage. The functional parameters of isolated Langendorff-perfused rat hearts were recorded before and after global 25 min ischemia and subsequent reperfusion. The infarct size was determined by a computerized planimetric method. The results showed that oxytocin produced negative chronotropic effect even at low concentrations (90-125 nmol/L). Perfusion with oxytocin before ischemia resulted in significant reduction of the infarct size (p < 0.01), which was about 66% smaller than that in the control group. To evaluate the functional mechanisms involved, further experiments were performed under conditions of constant heart rate. The lower dose of oxytocin (90 nmol/L), which was ineffective in spontaneously beating hearts, induced a significant decrease of contractility. Elimination of the negative chronotropic effect of oxytocin prevented its cardioprotective action. In conclusion, our results demonstrated an attenuation of the infarct size in oxytocin-treated hearts, indicating a cardioprotective effect of oxytocin. The data suggest that the negative chronotropic action of oxytocin participates in its protective effects on ischemia-reperfusion-induced myocardial injury. Key words: cardioprotection, infarction, heart, ischemia, oxytocin, in vitro, peptide. Parmi les pathologies cardiovasculaires, la cardiopathie ischemique est associee aux problemes de sante graves et pourrait etre a l'origine d'une lesion et (ou) d'une insuffisance cardiaque. La presente etude a eu pour but de verifier l'hypothese que le neuropeptide oxytocine induit des effets cardioprotecteurs contre la lesion myocardique induite par l'ischemie/reperfusion. La taille de l'infarctus a ete determinee par une methode planimetrique informatisee. Les parametres fonctionnels du coeur de rat isole et perfuse selon la methode de Langendorff ont ete enregistres avant et apres une ischemie globale de 25 min suivie d'une reperfusion. Les resultats montrent que l'oxytocine a produit un effet chronotrope meme a faibles concentrations (90-125 nmol/L). Une perfusion d'oxytocine avant l'ischemie a provoque une reduction significative de la taille de l'infarctus (p < 0,01), qui a ete environ 66 % plus faible que celui observe chez le groupe temoin. Pour evaluer le mecanisme fonctionnel implique, d'autres experience ont ete effectuees dans des conditions de frequence cardiaque constante. La plus faible dose d'oxytocine (90 nmol/L), qui a ete inefficace dans les coeurs battant spontanement, a induit une diminution importante de la contractilite. L'elimination de l'effet chronotrope negatif de l' oxytocine a prevenu son action cardioprotectrice. Ainsi, les presents resultats demontrent une attenuation de la taille de l'infarctus dans les coeurs traites a l'oxytocine, ce qui denote un effet cardioprotecteur du neuropeptide. Les resultats obtenus donnent a penser que l'action inotrope negative de l'oxytocine pourrait participer a ses effets protecteurs contre la lesion myocardique induite par l'ischemie/reperfusion. Mots-cles : cardioprotection, infarctus, coeur, ischemie, oxytocine, in vitro, peptide. [Traduit par la Redaction], Introduction Although several studies have indicated that oxytocin modulates cardiovascular function, the results are not consistent. Oxytocinergic neurons are present in various brain areas related to cardiovascular regulation (Buijs 1983; [...]

The neurohypophysial hormone oxytocin (OT), synthesized in magnocellular paraventricular (PVN) and supraoptic (SON) nuclei, is well known for its effects in lactation. Our previous studies showed that central OT receptor (OTR) binding is increased during gestation and that blockade of central OTRs, specifically during mid-late gestation, causes a delay in OT release during suckling and reduces weight gain in pups, suggesting decreased milk delivery. In the present study, we tested whether central OTR blockade during late gestation disrupts the gestation-related plasticity in intrinsic membrane properties. Whole cell current-clamp recordings were performed in OT neurons from pregnant rats (19-22 days in gestation) that were infused with an OTR antagonist (OTA) or artificial cerebrospinal fluid (aCSF) and from virgin rats infused with aCSF into the third ventricle via an osmotic minipump beginning on days 12-14 of gestation. The amplitudes of both [Ca.sup.2]+-dependent afterhyperpolarizations (AHPs), an apamin-sensitive medium AHP (mAHP) and an apamin-insensitive slow AHP (sAHP), were significantly increased during late gestation in control pregnant animals. However, the amplitude of the sAHP from pregnant rats treated with the OTA was significantly smaller than that of pregnant control rats and similar to that of virgins. These results indicate that the diminished efficiency in lactation due to OTR blockade may be partly a result of an altered sAHP that would shape OT bursting. These findings suggest that central actions of OT during late gestation are necessary for programming the plasticity of at least some of the intrinsic membrane properties in OT neurons during lactation. vasopressin; electrophysiology; hypothalamus; lactation; hyperpolarizing afterpotentials

A study to ascertain the extent to which obstetric practices were used in the third stage of labor was conducted. Results revealed that use of oxytocin in the third stage of labor had many beneficial effects for the mother and this information needs to be disseminated among birth attendants.

Laboratory mice drink little sucrose solution on initial exposure, but later develop a strong preference for sucrose over water that plateaus after a few days. Both the initial neophobia and later plateau of sucrose intake may involve central oxytocin (OT) signaling pathways. If so, then mice that lack the gene for OT [OT knockout (KO)] should exhibit enhanced initial and sustained sucrose intake compared with wild-type (WT) cohorts. To test this hypothesis, female OT KO and WT mice (11-13 mo old) were given a two-bottle choice between 10% sucrose and water available ad libitum for 4 days. On the first day, sucrose intake was 20-fold greater in OT KO mice compared with WT cohorts. The avid sucrose consumption by OT KO mice increased further on day 2 and was sustained at significantly higher levels than intake by WT mice. Enhanced initial and sustained sucrose intake also was observed in 5- to 7-mo-old male OT KO mice. The effect of genotype was observed over a range of sucrose concentrations and was maintained over at least 8 days of continual exposure. However, there was no effect of genotype on daily intake of sucrose-enriched powdered chow. These findings indicate that the genetic absence of OT in mice is associated with enhanced initial and sustained intake of sucrose solutions. Thus central OT pathways may normally participate in limiting initial intake of novel ingesta and may also participate in limiting intake of sweet, highly palatable familiar ingesta. sugar; palatability; overeating; satiety

Female mice can learn to respond to distress calls from young mice--an ability that has now been found to be improved through signalling by the hormone oxytocin in the left [...]