The Effects of Intra-Hippocampal Injection of Somatostatin and GABA Receptor Antagonist on Learning and Memory in Male Rats

Introduction: The hippocampus is a key brain region involved in learning and memory. Somatostatin is a neuropeptide that inhibits growth hormone release and modulates neuronal excitability, while GABA is a major inhibitory neurotransmitter in the central nervous system. The aim of this study was to investigate the effects of intra-hippocampal injection of somatostatin and its interaction with GABA receptor antagonist on passive avoidance memory and motor coordination (balanced memory) in male rats. Materials and Methods: Twenty-five male Wistar rats weighing ۲۲۰-۲۵۰ g will be randomly divided into five groups. The first group will receive saline as the control. The second, third, and fourth groups will receive intra-hippocampal injections of ۱, ۲, and ۴ micrograms of somatostatin, respectively. The fifth group will receive ۴ micrograms of somatostatin and ۲ micrograms of GABA receptor antagonist. Passive avoidance memory will be assessed using the shuttle box test, and balanced memory will be evaluated using the rotarod apparatus at baseline, and at ۱, ۳, and ۲۴ hours after drug administration. Data will be analyzed using SPSS software with repeated measures ANOVA and post hoc Tukey test. Results: The results are expected to show that intra-hippocampal injection of somatostatin significantly enhances passive avoidance memory in a dose-dependent manner compared to the control group. Co-administration with GABA receptor antagonist is hypothesized to further improve memory performance. However, somatostatin may cause a mild decrease in motor balance performance, which could be partially restored by GABA receptor antagonist co-injection. Conclusion: Somatostatin may improve memory retention through its modulatory effects on hippocampal neurons, and the interaction with GABAergic inhibition may influence motor coordination. These findings may contribute to a better understanding of peptide-based mechanisms in learning and memory.

کلیدواژه ها:

Somatostatin ، GABA receptor antagonist ، Passive avoidance memory ، Balanced memory ، Hippocampus