The purpose of this research is to develop compounds as tools to study opioid receptors. These receptors are proteins which are responsible for both the beneficial and the undisirable effects of narcotic analgesics such as morphine. However, not all opioid receptors are identical and this has complicated the study of this receptor group. Since the demonstration of these multiple opioid receptors about fifteen years ago, numerous compounds have been prepared in attempts to differentiate the receptor types. To further complicate the issue, endogenous morphine-like substances have been isolated from animals. These compounds, opioid peptides, are fragments of other proteins and appear to be involved in a number of physiological functions including pain sensation. This research involves the preparation of derivatives of one of the opioid peptides, dynorphin. This opioid interacts with kappa-opioid receptors which are distinct from morphine receptors. The study of kappa opioid receptors may lead to the development of better nonaddictive analgesics. The opioids are synthesized containing 'affinity labels' which cause the synthetic opioid to permanently bind to the receptor. In this way, any neuroscientists or pharmacologist may use these new peptides to differentiate between the various types of opioid receptors.
