Neuronostatin (NST) is a 13 amino acid peptide encoded in the somatostatin (SOM) pro-hormone. It was recently discovered and it is produced throughout the body, in particular in brain areas known to be important in metabolic and autonomic regulation. It has been shown that NST have similar effects to SOM in feeding behavior effects; however, NST effects on memory, hippocampal excitability and anxiety have not been described. In the present work we investigated the effect of intra-hippocampal NST administration upon memory retention, hippocampal excitability, anxiety-like and feeding behavior in Wistar male rats.
In our study, we have demonstrated acute intra-hippocampal NST administration induces anxiolytic effects and impairs memory retention, but it did not induce changes in food intake and drinking. We have also shown that NST 0.3 nmol/µl administration into the CA1 hippocampus decreased the threshold values to generate LTP, while that NST 3.0 nmol/µl administration blocked the LTP generation.
These results provide behavioral evidence that NST may modulate higher brain functions, suggesting that the peptide influences anxiolytic and memory processes that involve the hippocampus and that the hippocampus don´t participates in the NST effects on hunger at the doses studied.
