Arginine vasopressin facilitates reversal learning in albino, but not hooded rats

Male Holtzman albino and Long-Evans hooded rats were administered one microgram of arginine vasopressin (AVP) or a placebo each day after the acquisition trials of a visual white-black discrimination. Animals were then trained in the reversal of the discrimination. Performance was assessed by the number of trials to criterion during acquisition and reversal. Treatment with AVP resulted in significantly fewer trials to criterion during reversal learning in Holtzman albino rats, but did not influence reversal learning in Long-Evans hooded rats. These results provide evidence that AVP may have differential actions on memory processes in different strains of rats.