Neurokinin peptides are small protein-like molecules that play a crucial role in the nervous system. They are involved in various physiological processes, including pain perception, inflammation, and the regulation of mood. The most well-known neurokinin peptides include substance P, neurokinin A, and neurokinin B, each having specific functions and receptors in the body. These peptides interact with neurokinin receptors, which are found in the brain and other tissues. By binding to these receptors, neurokinin peptides can influence behaviors such as stress response and anxiety. Their study is important for understanding conditions like chronic pain and mood disorders.