Salvinorin B Mesylate (Mesyl Sal B) is primarily used in research settings to study the kappa opioid receptor (KOR) system. It serves as a valuable tool for understanding the pharmacological and neurological effects of kappa opioid receptor activation. Researchers utilize it to explore its potential in modulating pain, mood, and addiction pathways. Its high selectivity for KOR makes it particularly useful in distinguishing the roles of this receptor from other opioid receptors in various physiological and behavioral processes. Additionally, it aids in the development of novel therapeutic agents targeting KOR for conditions such as chronic pain, depression, and substance use disorders.