Ghrelin (Ghr) is a peptide produced peripherally and centrally. It participates in the modulation of different biological

processes. In our laboratory we have shown that a) Ghr administration, either intracerebroventricular or directly into

the hippocampus enhanced memory consolidation in a step down test in rats b) the effect of Ghr upon memory

decreases in animals pretreated with a 5-HT reuptake inhibitor, Fluoxetine, suggesting that Ghr effects in the

hippocampus could be related to the availability of 5-HT. It has been demonstrated that Ghr inhibits 5-HT release

from rat hypothalamic synaptosomes. Taking in mint these evidences, we studied the release of radioactive 5-HT

to the superfusion medium from hippocampal slices treated with two doses of Ghr (0.3 and 3nm/ml).Ghr inhibited

significantly the 5-HT release in relation to those superfused with artificial cerebrospinal fluid (ACSF) (H =9.48, df= 2,

significantly the 5-HT release in relation to those superfused with artificial cerebrospinal fluid (ACSF) (H =9.48, df= 2,

p ¡Ü 0.05). In another set of experiments, Ghr was infused into the CA1 area of hippocampus of the rats immediately

after training in the step down test and the 5-HT release from slices was studied 24 hs after Ghr injection showing

that in this condition also the 5-HT release was inhibited (H = 11.72, df=1 , p ¡Ü 0.05). In conclusion, results provide

additional evidence about the neurobiological bases of Ghr action in hippocampus.

significantly the 5-HT release in relation to those superfused with artificial cerebrospinal fluid (ACSF) (H =9.48, df= 2,

p ¡Ü 0.05). In another set of experiments, Ghr was infused into the CA1 area of hippocampus of the rats immediately

after training in the step down test and the 5-HT release from slices was studied 24 hs after Ghr injection showing

that in this condition also the 5-HT release was inhibited (H = 11.72, df=1 , p ¡Ü 0.05). In conclusion, results provide

additional evidence about the neurobiological bases of Ghr action in hippocampus.

significantly the 5-HT release in relation to those superfused with artificial cerebrospinal fluid (ACSF) (H =9.48, df= 2,

p ≤ 0.05). In another set of experiments, Ghr was infused into the CA1 area of hippocampus of the rats immediately

after training in the step down test and the 5-HT release from slices was studied 24 hs after Ghr injection showing

that in this condition also the 5-HT release was inhibited (H = 11.72, df=1 , p  0≤.05). In conclusion, results provide

additional evidence about the neurobiological bases of Ghr action in hippocampus.