The effect of pergolide on cognitive performance of young and middle-aged rats.

In this study, we investigated the effect of pergolide, a dopaminergic agonist, on cognitive ability in young and middle-aged rats using the Morris Water Maze (MWM). Pergolide 0.5/mg/day i.p. was administered to young and middle-aged rats, whereas only vehicle was given to their age-matched controls. During the acquisition period of 6 days, young rats showed normal escape latency pattern, which was not affected by pergolide. Middle-aged rats, however, showed poor escape latency pattern, and this poor pattern was also not affected by pergolide. On the 7th day, pergolide decreased retention time of young rats compared to control values. Middle-aged rats also showed reduced retention time. In contrast to the findings of young rats, retention time was not affected by pergolide in middle-aged rats. We concluded that pergolide does not alter escape latency at any age. It has a negative effect on retention time of young rats, whereas it has no effect on middle-aged ones.