Conditioned context aversion learning in the laboratory mouse

Abstract

It is well known that pairing of large contextual changes with illness can cause conditioned context aversion in laboratory rats. The aim of present study was to develop a paradigm to study this phenomenon in laboratory mice, a species widely employed in neurobehavioral studies. Genetically heterogeneous mice, drinking from plastic bottles in the colony room, learned to avoid glass bottles after a single conditioning trial when drinking from these was paired with injections of lithium chloride. The aversion was independent of any difference in the taste of water in plastic vs. glass bottles. When the variation in the visual stimulus was less distinct, development of a strong aversion required two conditioning trials and was not retained as well. The results also showed that conditioned context aversion, just like conditioned taste aversion, could also be developed across a 30-minute CS-UCS delay. The fact that taste was not a factor in distinguishing drinking from glass and plastic water bottles raises the possibility that, contextual stimuli, not taste, may have been the CS when rats (in Garcia's original experiments) avoided drinking from plastic bottles that had been paired with radiation. The development of contextual aversion conditioning protocols for mice will enable the molecular resources available for this species to be exploited. Furthermore, representation of the CS by discrete rather than the multimodal CSs typically used in most studies on contextual conditioning offers more focus when considering its neuroanatomical basis.

Hypothalamic control of interoceptive hunger

“…to induce gastrointestinal malaise and returned to home cages. 77,97 Gel intake was determined. In the second session, mice were returned to the test chamber with access to caloric gel and received 20-Hz photostimulation (1 s on, 3 s off) for 1 h; gel intake was determined at the end of the session.…”

Acquisition and retention of conditioned aversions to context and taste in laboratory mice

“…The duration of retention was not tested for this combination of stimuli (GB vs. GT) in our earlier experiment, but the length of retention shown here is longer than was found when maintenance and CS tubes only differed in the brightness of a piece of tape attached to the tubes (Kislal & Blizard, 2016, Experiment 3). In our earlier experiment (Kislal & Blizard, 2016, Experiment 3), we found substantial nonspecific aversion when maintenance and CS tubes differed by the brightness of a piece of tape but little evidence when the difference was more substantial (switching from glass bottle to graduated tubes; see Fig. 4).…”

“…The results of Experiment 1 with a different stock of mice than previously used (Kislal & Blizard, 2016) show that pairing illness with small changes in the cage environment can result in specific aversion that lasts approximately 4 weeks. In the present case, both the immediate and delay experimental groups retained the aversion to a similar degree.…”

“…Our recent studies with outbred mice from a cross of C57BL/ 6J and DBA/2J strains (Kislal & Blizard, 2016) showed that inducing illness (resulting from LiCl injections) following ingestion of water from a novel container resulted in strong inhibition of drinking following subsequent presentations. The results from the current experiments with mice derived from a different outbred cross (derived from LG and SM strains) extended these findings and added important information about the duration of retention of conditioned context aversions.…”

“…Our recent studies using genetically heterogeneous mice have shown that pairing illness with drinking from a novel water container in the home cage also results in CCA (Kislal & Blizard, 2016). Mice were able to form strong aversions after a single pairing of the CS with lithium chloride (LiCl) when the maintenance container was a plastic bottle and the CS was a glass bottle (Kislal & Blizard, 2016, Experiment 1), or, when the maintenance container was a glass bottle and the CS, a graduated tube (Kislal & Blizard, 2016, Experiment 2).…”