Novel Receptor Active Substances

Because the pnnciples of competitive binding assays for this last application are identical to those of the RRA, they will be discussed together in the following sections. For simplicity, both applications of ligand binding techniques are referred to as RRAs.  

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The existence of binary toxins raises the possibility that unique chimeric substances can be formed that have implicit within them "receptors-on-demand". The underlying concepts to support this premise are as follows. First, the light chain component of C2 toxin could be modified so that it no longer expressed enzymatic activity. When so modified, it could be envisioned as a tissue-targeting domain, as explained below. Next, a novel pharmacologically active domain could be attached to the light chain. 

Nociceptin (orphanin FQ) is a novel neuropeptide whose actions have yet to be completely elucidated. However, stimulation of the nociceptin receptor has been implicated in the modulation of many neurobehavioral processes, including pain, substance dependence, sexual behavior, anxiety, locomotor activity, learning capacity, memory, and adaptation to stressful stimulus [1-6]. Continued research in this area has the potential to lead to a new class of drugs for pain medicine and beyond. 

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