Diabetic rats prefer glucose-paired flavors over fructose-paired flavors.
Prior studies indicate that glucose has a more potent postingestive reinforcing effect than fructose. The role of insulin in this effect was examined by comparing sugar-conditioned flavor preferences in normal and streptozotocin-diabetic rats. In Experiment 1, diabetic rats, like normal rats, preferred a cue flavor that had been mixed into 8% glucose solution over a flavor mixed with 8% fructose. Both taste and postingestive properties of glucose may have contributed to this preference. Experiment 2 evaluated postingestive reinforcement by pairing cue flavors with intragastric infusions of glucose and fructose. Both diabetics and normals acquired a preference for the flavor paired with intragastric 16% glucose infusions over the flavor paired with 16% fructose infusions although the preference was somewhat smaller in the diabetic rats. Taken together, the results indicate that a normal insulin secretory response to glucose is not required for glucose-conditioned flavor preference. The diabetic rats' reduced flavor preference in Experiment 2 suggests that insulin may play some role in glucose conditioning although this may be secondary to alterations in gastrointestinal motility characteristic of diabetic animals.
Ackroff
K
K
Department of Psychology, Brooklyn College and the Graduate School of New York City University, 11210, USA.
Sclafani
A
A
Axen
K V
KV
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D005518:Food Preferences / Q000502:physiology* / Q000523:psychology; D005632:Fructose; D005947:Glucose; D007328:Insulin / Q000502:physiology; D051381:Rats; D012054:Reinforcement, Psychology; D013311:Streptozocin; D013649:Taste
D007328:Insulin; D005632:Fructose; D013311:Streptozocin; D005947:Glucose