What is the primary site of central pathway involvement in chemotherapy-induced nausea and vomiting (CINV)?

The central pathway primarily involved in chemotherapy-induced nausea and vomiting (CINV) is the brain. Specifically, the chemoreceptor trigger zone (CTZ) and the vomiting center, located in the medulla oblongata, are critical areas that mediate the emetic response to chemotherapeutic agents. When chemotherapy drugs are administered, they can interact with neurotransmitters and receptors in the brain, particularly serotonin (5-HT) and dopamine receptors, triggering nausea and the vomiting reflex.

Understanding this central role emphasizes that while peripheral organs like the stomach and intestines can contribute to the sensation of nausea through other mechanisms, it is the brain that integrates these signals and coordinates the vomiting response. This distinction highlights the importance of targeting central pathways when developing antiemetic therapies to prevent or manage CINV effectively.