Relationship between the grades of a learned aversive-feeding response and the dopamine contents in Lymnaea

Biology Open

Ken Lukowiak¹  Mugiho Kaneda²  Etsuro Ito²  Dai Hatakeyama²  Takayuki Watanabe³  Hitoshi Aonuma³ 

[1] Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada T2N 1N4;Laboratory of Functional Biology, Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Sanuki 769-2193, Japan;Research Center of Mathematics for Social Creativity, Research Institute for Electronic Science, Hokkaido University, Sapporo 060-0811, Japan;

关键词: Conditioned taste aversion;    Dopamine;    Food deprivation;    Long-term memory;    Lymnaea;   

DOI  :  10.1242/bio.021634

来源: DOAJ

【 摘 要 】

The pond snail Lymnaea learns conditioned taste aversion (CTA) and remembers not to respond to food substances that initially cause a feeding response. The possible relationship between how well snails learn to follow taste-aversion training and brain dopamine contents is not known. We examined this relationship and found the following: first, snails in the act of eating just before the commencement of CTA training were poor learners and had the highest dopamine contents in the brain; second, snails which had an ad libitum access to food, but were not eating just before training, were average learners and had lower dopamine contents; third, snails food-deprived for one day before training were the best learners and had significantly lower contents of dopamine compared to the previous two cohorts. There was a negative correlation between the CTA grades and the brain dopamine contents in these three cohorts. Fourth, snails food-deprived for five days before training were poor learners and had higher dopamine contents. Thus, severe hunger increased the dopamine content in the brain. Because dopamine functions as a reward transmitter, CTA in the severely deprived snails (i.e. the fourth cohort) was thought to be mitigated by a high dopamine content.

【 授权许可】

Unknown