Bombesin is a gastrin-releasing peptide analog that binds bombesin and GRP receptors. Derivatives of bombesin are currently under investigation as cancer imaging tools, as bombesin receptors are often overexpressed in tumor tissues. Bombesin itself exhibits neuromodulatory, hepatoprotective, cardiomodulatory, and vasoconstrictive activities. Bombesin increases the frequency and amplitude of IPSCs in the entorhinal cortex, likely due to Ca2+-mediated increases in GABA release. In animal models of liver disease, bombesin increases proliferation of oval cells and hepatocytes, increases levels of glutathione, and decreases portal endotoxemia. Bombesin also exhibits pressor-like effects, increasing mean arterial pressure, blood pressure, and heart rate.