Higher sensitivity to ethanol's aversive properties in WLP (Warsaw Low Preferring) vs. WHP (Warsaw High Preferring) rats

Edyta Wyszogrodzka; Wanda Dyr; Agnieszka Siwińska-Ziółkowska; Pawel Mierzejewski

doi:10.1016/j.alcohol.2020.12.002

Higher sensitivity to ethanol's aversive properties in WLP (Warsaw Low Preferring) vs. WHP (Warsaw High Preferring) rats

Alcohol. 2021 Feb:90:67-73. doi: 10.1016/j.alcohol.2020.12.002. Epub 2020 Dec 19.

Authors

Edyta Wyszogrodzka¹, Wanda Dyr¹, Agnieszka Siwińska-Ziółkowska², Pawel Mierzejewski³

Affiliations

¹ Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, ul. Sobieskiego 9, 02-957 Warsaw, Poland.
² Department of Forensic Medicine, Warsaw Medical University, ul. Oczki 1, 02-007 Warsaw, Poland.
³ Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, ul. Sobieskiego 9, 02-957 Warsaw, Poland. Electronic address: mierzeje@ipin.edu.pl.

PMID: 33352200
DOI: 10.1016/j.alcohol.2020.12.002

Abstract

Ethanol can have both an aversive and rewarding effect, which may have a significant relationship to its individual preference. So far, the reasons for the high and low ethanol preference in the WHP (Warsaw High Preferring) and WLP (Warsaw Low Preferring) lines have not been found. WHP rats spontaneously drink over 5 g/kg/day of ethanol, while WLP rats drink under 2 g/kg/day. The purpose of the work was to study the sensitivity of WHP and WLP rats to the aversive effects of ethanol at doses of 1.5 g/kg and 2.0 g/kg in the conditioned taste aversion (CTA) procedure. Lower doses (0.5 and 1.0 g/kg, i.p. [intraperitoneally]) were tested earlier and only 1.0 g/kg produced a slight aversion in WLP rats. The secondary aim was to check the additional potential factors (blood ethanol concentration, pain sensitivity, anxiety-related behavior, learning, and memory) that may constitute an important differentiating feature of the WHP and WLP lines. For this purpose, the following tests were conducted: blood ethanol concentration, novel object recognition (NOR), flinch-jump, hot-plate, and elevated plus maze (EPM). The 1.5 g/kg i.p. dose of ethanol caused the development of an aversion only in WLP rats and the aversion extinguished in the post-conditioning phase. The 2.0 g/kg i.p. dose of ethanol resulted in the development of an aversion in both the tested groups, with the aversion being maintained throughout the whole post-conditioning period only in the WLP rats. There were no differences between the lines in terms of the blood ethanol concentration and the EPM tests. WHP rats had a higher pain sensitivity compared to WLP rats in flinch-jump and hot-plate tests. WLP rats showed a shorter exploration time for both objects compared to WHP in the NOR test. In conclusion, WHP and WLP rats differ in sensitivity to the aversive effects of ethanol. This difference may partially explain their opposite ethanol preference.

Keywords: Warsaw High Preferring rats; Warsaw Low Preferring rats; conditioned taste aversion; ethanol aversion; ethanol preference.

Publication types

Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

Alcohol Drinking*
Animals
Anxiety
Avoidance Learning*
Conditioning, Classical*
Ethanol / administration & dosage
Rats

Substances

Ethanol