Oxytocin and Rodent Models of Addiction

Clinical Trials for Opioid Use Disorder

This chapter describes recent clinical trials for opioid use disorder (OUD), an area that has rapidly accelerated in response to the opioid overdose crisis in the USA and newly appropriated funding. Trials involve a wide range of compounds including cannabinoids and psychedelics, new and existing compounds targeting domains emerging from addiction neuroscience, agents repurposed from other indications, and novel strategies including vaccines, enzymes, and other biologicals. In parallel, new formulations of existing compounds offer immediate promise, as do a variety of web-based interventions and smartphone-delivered apps. Trials focused on implementing existing effective interventions in mainstream healthcare settings, and others focused on special populations, e.g., adolescents, criminal justice, pregnant women, native Americans, etc., have the potential to vastly expand treatment in the near term. Given the range of ongoing and recent trials, this chapter is not intended to be an exhaustive review but rather to present an overview of approaches within the framework of the opioid treatment cascade and the context of current OUD pharmacotherapies.

Oxytocin attenuates stress-induced reinstatement of alcohol seeking behavior in male and female mice

RATIONALE

The neuropeptide oxytocin (OXT) has emerged as a potential therapeutic intervention in the treatment of both alcohol use disorder (AUD) and stress-related psychiatric illnesses.

OBJECTIVES

The present study evaluates the effects of systemically administered (intraperitoneal (i.p.)) OXT treatment on alcohol relapse-like behavior in male and female mice.

METHODS

Adult male and female C57BL/6J mice were trained to lever respond in operant conditioning chambers for alcohol in daily self-administration sessions. Once lever responding and alcohol intake stabilized, mice were tested under extinction conditions for 14 days before reinstatement testing. All mice underwent stress-induced reinstatement testing using either predator odor (2,3,5-trimethyl-3-thiazoline (TMT)) or the α-2 adrenergic receptor agonist yohimbine. In study 1, mice were exposed to TMT for 15 min and then immediately placed into operant conditioning chambers to examine alcohol-seeking behavior under extinction conditions. At 30 min prior to test session, separate groups of mice were injected with vehicle or OXT (0.1, 0.5, 1 mg/kg). In study 2, mice were injected with yohimbine (0.3, 0.625 mg/kg) 1 h prior to reinstatement testing. At 30 min post-yohimbine injection, mice are injected (i.p.) with vehicle or OXT (1 mg/kg).

RESULTS

OXT attenuated alcohol-seeking behavior in a dose-related manner in male and female mice in response to acute challenge with a predator odor. Additionally, OXT administration produced a similar decrease in alcohol relapse-like behavior triggered by the pharmacological stressor yohimbine in both sexes.

CONCLUSIONS

Systemic oxytocin administration attenuates stress-induced reinstatement of alcohol seeking in male and female mice.

Neurobiological Risk Factors for the Development of Internet Addiction in Adolescents

The sudden appearance and spread of Internet addiction in adolescent populations, in association with the rapid escalation of consumed Internet content and the broad availability of smartphones and tablets with Internet access, is posing a new challenge for classical addictology which requires urgent solutions. Like the majority of other psychopathological conditions, pathological Internet addiction depends upon a group of multifactor polygenic conditions. For each specific case, there is a unique combination of inherited characteristics (nervous tissue structure, secretion, degradation, and reception of neuromediators), and many are extra-environment factors (family-related, social, and ethnic-cultural). One of the main challenges in the development of the bio-psychosocial model of Internet addiction is to determine which genes and neuromediators are responsible for increased addiction susceptibility. This information will herald the start of a search for new therapeutic targets and the development of early prevention strategies, including the assessment of genetic risk levels. This review summarizes the literature and currently available knowledge related to neurobiological risk factors regarding Internet addiction in adolescents. Genetic, neurochemical and neuroimaging data are presented with links to actual pathogenetic hypotheses according to the bio-psychosocial model of IA forming.

Social modulation of drug use and drug addiction

This review aims to demonstrate how social science and behavioral neurosciences have highlighted the influence of social interactions on drug use in animal models. In neurosciences, the effect of global social context that are distal from drug use has been widely studied. For human and other social animals such as monkeys and rodents, positive social interactions are rewarding, can overcome drug reward and, in all, protect from drug use. In contrast, as other types of stress, negative social experiences facilitate the development and maintenance of drug abuse. However, interest recently emerged in the effect of so-called "proximal" social factors, that is, social interactions during drug-taking. These recent studies have characterized the role of the drug considered, the sharing of drug experience and the familiarity of the peer which interaction are made with. We also examine the few studies regarding the sensorial mediator of social behaviors and critically review the neural mediation of social factors on drug use. However, despite considerable characterization of the factors modulating distal influences, the mechanisms for proximal influences on drug use remain largely unknown. This article is part of the Special Issue entitled 'The neuropharmacology of social behavior: from bench to bedside'.

[Oxitocin is a hormone of trust and emotional attachment: the influence on behavior of children and adolescents]

This review presents current data on the mechanisms of production and reception of oxytocin and its effect on the socio-emotional aspects of behavior in different age periods of childhood and adolescence. The main hormonal role of oxytocin is to regulate the process of carrying a fetus, childbirth and lactation, as well as the establishment of social connections from the infancy period (connection with parents with a child) throughout childhood to adolescence and adult periods of life. Its central action takes the most important part in cognitive, emotional and behavioral processes. In addition, oxytocin plays a role in the regulation of food and sexual behavior, in the mechanisms of visceral hypersensitivity and pain perception. The analysis of publications covering the most important role of oxytocin in the formation of the emotional interaction between parents and children in different age periods: infancy, preschool and adolescence was carried out. A brief analysis of genetically determined features of the production and reception of oxytocin and their role in the regulation of behavioral responses is presented. In addition, the review briefly highlights aspects of the likely involvement of oxytocin in the mechanisms of formation of certain psychopathological conditions in children and adolescents.