Ghrelin increases anxiety-like behavior and memory retention in rats

Area of Science:

• Neuroendocrinology
• Behavioral Neuroscience
• Molecular Psychiatry

Background:

• Ghrelin is a peptide hormone primarily known for stimulating food intake.
• Its central behavioral effects beyond appetite regulation remain largely unexplored.
• Understanding ghrelin's broader neurobiological functions is crucial for metabolic and psychiatric research.

Purpose of the Study:

• To investigate the central behavioral effects of ghrelin on anxiety and memory.
• To determine if ghrelin influences anxiety-like behaviors and memory retention in a rodent model.
• To explore the dose-dependent effects of ghrelin administration.

Main Methods:

• Intracerebroventricular (ICV) administration of ghrelin in adult male rats.
• Behavioral assessments included the open-field test, elevated plus-maze, and step-down inhibitory avoidance test.
• Food intake was monitored following ghrelin administration.

Main Results:

• Ghrelin administration induced anxiogenic effects, evidenced by increased freezing in the open field and reduced exploration of open spaces in the plus-maze.
• Ghrelin significantly increased memory retention in the step-down test in a dose-dependent manner.
• A rapid and sustained increase in food intake was observed post-administration.

Conclusions:

• Ghrelin acts as an anxiogenic agent in rats.
• Ghrelin enhances memory retention, suggesting a potential role in hippocampal function.
• These findings highlight novel roles for ghrelin in central nervous system regulation beyond appetite control.