Article

Consequences of early experiences and exposure to oxytocin and vasopressin are sexually dimorphic.

Department of Psychiatry, Brain Body Center, University of Illinois at Chicago, Chicago, Ill. 60612, USA.
Developmental Neuroscience (Impact Factor: 2.45). 02/2009; 31(4):332-41. DOI: 10.1159/000216544
Source: PubMed

ABSTRACT In the socially monogamous prairie vole, we have observed that small changes in early handling, as well as early hormonal manipulations can have long-lasting and sexually dimorphic effects on behavior. These changes may be mediated in part by changes in parental interactions with their young, acting on systems that rely on oxytocin (OT) and arginine vasopressin (AVP). Knowledge of both endogenous and exogenous influences on systems that rely on OT and AVP may be helpful in understanding sexually dimorphic developmental disorders, such as autism, that are characterized by increased anxiety and deficits in social behavior.

Full-text

Available from: Carol Sue Carter, Jul 07, 2014
1 Follower
 · 
136 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objective Preclinical studies indicate that oxytocin is anorexigenic and has beneficial metabolic effects. Oxytocin effects on nutrition and metabolism in humans are not well defined. It was hypothesized that oxytocin would reduce caloric intake and appetite, and alter levels of appetite-regulating hormones. Metabolic effects of oxytocin were also explored.MethodsA randomized, placebo-controlled crossover study of single-dose intranasal oxytocin (24 IU) in 25 fasting healthy men was performed. After oxytocin/placebo, subjects selected breakfast from a menu, and were given double portions. Caloric content of food consumed was measured. Visual analog scales were used to assess appetite and blood was drawn for appetite-regulating hormones, insulin, and glucose before and after oxytocin/placebo. Indirect calorimetry assessed resting energy expenditure (REE) and substrate utilization.ResultsOxytocin reduced caloric intake with a preferential effect on fat intake and increased levels of the anorexigenic hormone cholecystokinin without affecting appetite or other appetite-regulating hormones. There was no effect of oxytocin on REE. Oxytocin resulted in a shift from carbohydrate to fat utilization and improved insulin sensitivity.Conclusions Intranasal oxytocin reduces caloric intake and has beneficial metabolic effects in men without concerning side effects. The efficacy and safety of sustained oxytocin administration in the treatment of obesity warrants investigation.
    Obesity 04/2015; 23(5). DOI:10.1002/oby.21069 · 4.39 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Repeated separation from pups results in anxiety and depression-like behaviors in mothers. This level of attachment has also been established between fathers and pups in monogamous rodents. We hypothesized that brief and lengthy separation from their pups would affect emotion, social behavior and neuroendocrine parameters in socially monogamous male mandarin voles (Microtus mandarinus). The results indicate that brief pup separation (BPS) of 15min/day significantly reduced the percentage of time spent in the central area, total distance and total transition in open field tests. BPS resulted in increased sniffing and self-grooming in fathers, but reduced attacking and climbing. Long pup separation (LPS) of 3h/day suppressed attacking, sniffing, no-social investigating and digging in fathers, but increased time in immobile in social interaction and forced swimming tests. LPS upregulated levels of central oxytocin (OT) and vasopressin (AVP), serum corticosterone (CORT); BPS increased central OT and serum corticosterone only. These findings show that BPS and LPS are critical stressors for fathers and alter anxiety and depression-like and social behaviors in monogamous mandarin voles. These changes in behaviors may be associated with alteration in OT, AVP and CORT. Copyright © 2014 Elsevier Inc. All rights reserved.
    Physiology & Behavior 11/2014; 139C:89-96. DOI:10.1016/j.physbeh.2014.11.017 · 3.03 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Peripherally administered oxytocin (OT) has produced antipsychotic drug (APD)-like effects in animal tests that are predictive of APD efficacy. However, these effects have mainly been demonstrated using animal models of schizophrenia-like deficits in prepulse inhibition (PPI) of the startle reflex. Another schizophrenia-relevant abnormality that is the basis of a predictive animal test for APD efficacy is deficient latent inhibition (LI). LI is the normal suppression of a classically conditioned response when the subject is pre-exposed to the conditioned stimulus (CS) before it is paired with the unconditioned stimulus (UCS). Conditioned taste aversion (CTA), the normal avoidance of ingesting a food or liquid by animals when its taste is associated with an aversive experience, was used to test whether OT facilitates LI consistent with APDs. Brown Norway rats, known to naturally display attenuated LI, were aversively conditioned on two consecutive exposures to flavored drinking water (0.1% saccharin) by pairing it with malaise-inducing lithium chloride injections. Concurrent with conditioning, rats received subcutaneous OT (0.02, 0.1, 0.5mg/kg) or saline. Some rats were pre-exposed to the flavored water prior to its aversive conditioning (pre-exposed) while others were not (non pre-exposed). Two days after aversive conditioning the amount of flavored water consumed during a 20-min session was recorded. As expected, LI, defined as greater consumption by pre-exposed vs. non pre-exposed rats was only weakly exhibited in Brown Norway rats and OT enhanced LI by reducing CTA in pre-exposed rats in a dose-dependent manner, with the 0.02mg/kg dose producing the strongest effect. The facilitation of LI by OT is consistent with the effects produced by APDs and provides further support for the notion that OT has therapeutic potential for schizophrenia. Copyright © 2014 Elsevier B.V. All rights reserved.
    Behavioural Brain Research 10/2014; 278C:424-428. DOI:10.1016/j.bbr.2014.10.023 · 3.39 Impact Factor