Review of research on alcohol dependence in a model of mice selected for high and low stress-induced analgesia

Abstract

Authors' contribution Wkład autorów: A. Study design/planning zaplanowanie badań B. Data collection/entry zebranie danych C. Data analysis/statistics dane-analiza i statystyki D. Data interpretation interpretacja danych E. Preparation of manuscript przygotowanie artykułu F. Literature analysis/search wyszukiwanie i analiza literatury G. Funds collection zebranie funduszy Summary Decades of studies on alcohol dependence showed that it is a very complex and multifactorial disorder. Several receptor systems are involved in development and susceptibility to alcohol abuse; however, there are some which play a crucial role in its pathogenesis, e.g. dopaminergic or opioid system. In this paper, an effort is made to explain the role of endogenous opioid system activity in alcohol dependence. To achieve the goal, we use a unique model is used which shows mice lines that are divergently selected for high (HA) and low (LA) stress-induced analgesia. This process allowed for selecting individuals characterised by hyperactive (HA) or hypoactive (LA) opioid system. Basing on the performed experiments, we proved that delta opioid receptors play a critical role in the development of addiction. The most notable achievement is an unspecific reaction of mice with the hyperactive opioid system to naloxone-an unspecific opioid system antagonist, which is currently approved in the pharmacotherapy of dependent patients.

The Influence of Cross-Fostering on Alcohol Consumption and Depressive-Like Behaviors in HA and LA Mice: The Role of the Endogenous Opioid System

“…In the current study, we used the mouse model of distinct response to stress, obtained by a selection toward high (HA) and low analgesia (LA) induced by forced swimming, referred to as HA/LA model, reviewed elsewhere [18]. These mouse lines exhibit differences in endogenous opioid system activity, exhibiting different ethanol consumption levels.…”