Figure 1.

Schematic representation of the cocaine and glucose/saccharin self-administration experiments. The effects of TC and its control peptide (TE) were tested using a within-subjects Latin square design in which test days were separated by a drug-free (NT) day. During these NT days, rats had access to cocaine without drug treatment. Note: the animals in group A received TE followed by TC 2 experimental days later, whereas the animals in group B received TC followed by TE 2 experimental days later.