Loading…

Variation in the onset of CO2-induced anxiety in female Sprague Dawley rats

Carbon dioxide (CO 2 ) is commonly used to kill laboratory rats. Rats find CO 2 aversive and aversion varies between individuals, indicating that rats vary in CO 2 sensitivity. Healthy humans experience feelings of anxiety at concentrations similar to those avoided by rats, and these feelings are di...

Full description

Saved in:
Bibliographic Details
Published in:Scientific reports 2019-12, Vol.9 (1), p.1-8, Article 19007
Main Authors: Améndola, Lucía, Ratuski, Anna, Weary, Daniel M.
Format: Article
Language:English
Subjects:
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Carbon dioxide (CO 2 ) is commonly used to kill laboratory rats. Rats find CO 2 aversive and aversion varies between individuals, indicating that rats vary in CO 2 sensitivity. Healthy humans experience feelings of anxiety at concentrations similar to those avoided by rats, and these feelings are diminished by the administration of benzodiazepines. Our aim was to assess the effects of the benzodiazepine midazolam on individual thresholds of rat aversion to CO 2 . Six female Sprague Dawley rats were repeatedly exposed to CO 2 gradual-fill in approach-avoidance testing. The first three exposures were to a control-treatment followed by three exposures to midazolam (0.375 mg/kg). Within each treatment aversion to CO 2 was not affected by exposure number; however, tolerance increased from an average of 10.7% CO 2 avoided during control sessions, to 15.5% CO 2 avoided when treated with midazolam. These results indicate that rats experience anxiety when exposed to CO 2 , and that variation in rat CO 2 sensitivity is driven by individual differences in the onset of these feelings of anxiety. No rat tolerated CO 2 concentrations required to induce loss of consciousness.
ISSN:2045-2322
2045-2322
DOI:10.1038/s41598-019-55493-0