Opiate receptor ligands

Berry, S.C. Dawkins, S.L. and Lodge, D. Comparison of o-- and K -Opiate receptor ligands as excitatory amino acid antagonists. r J. Pharmacol 83 179-185, 1984b. 

This experiment represents a scenario when an organic lead compound is available. We chose morphine, a known opiate receptor ligand of non-peptide chemical nature, as a hypothetical lead compound. The averaged frequency distribution based on all four SA runs is obtained (data not shown). The most frequent building block was Dll. Building blocks DIO, D12, D14, and 03 were less frequent, but all above random expectation. 

Figure 3-6 Biologically active peptoids. Compound a Is an (i-adrenergic inhibitor, whde compound b is a /u-opiate receptor ligand.

Shibuya, j., Bowie, D., and Pert, C., 1977, Opiate receptor ligand in cerebrospinal fluid a simple radioreceptor assay requiring no preliminary purification, Proc. Soc. Neurosci. 3 460. 

The BZ stmcture also has provided a molecular scaffold for a number of peptide receptor ligands (26). Antagonists for the cholecystokinin (CCK-A) receptor, eg, devazepide (65), the thyrotropin-releasing hormone (TRH) receptor, eg, midazolam (66), and the /i -opiate receptor, eg, tifluadom (67), as well as a series of ras famyl transferase inhibitors, eg, BZA-2B (68) (30) have been identified (Table 4). 

Blume A. Interaction of ligands with the opiate receptors of brain membranes regulation by ions and nucleotides. Proc Natl Acad Sci USA 1978 ... 

Changing the amino acid sequence of the cloned receptors by mutating nucleotides within the receptor cDNAs has proven to be an effective mechanism by which to identify structural features of the receptors responsible for their unique functional properties. In particular, site-directed mutagenesis has been employed to determine the ligand binding domains of each opiate receptor. 

Neprilysin (enkephalinase, Endopeptidase-24.11, neutral endopeptidase, NEP, EC 3.4.24.11) bears considerable resemblance to other zinc-containing metallopeptidases it is an oligopeptidase that hydrolyzes enkephalins and a range of other active peptides. Enkephalins are endogenous ligands of opiate receptors, and the prolongation of their action via inhibition of enkephalinase... 

GPR7, GPR8 Opiates Somatostatine receptor ligands... 

Leysen, J.E., Gommeren, W., Niemegeers, C.J. [3H]Sufentanil, a superior ligand for mu-opiate receptors binding properties and regional distribution in rat brain and spinal cord, Eur. J. Pharmacol. 1983, 87, 209-225. 

Synthesis of 18F-opiates and 18F-steroids have been briefly reviewed also331. Biological studies of the above 18F-labelled receptor ligands in animals have been discussed briefly331,332. 

We started out our studies on amphibian opioid peptides in the wake of the explosion of research on mammalian endogenous ligands for opiate receptors. We asked ourselves whether the never disappointing amphibian skin contained related molecules. The question was reasonably posed in the light of the outcome of our previous, yearlong research showing that amphibian skin peptides often had counterparts in mammalian CNS and gastrointestinal tract [1]. 

Cannabinoids may share at least some common neuronal mechanisms with opioid compounds. Studies of intracellular events associated with ligand binding to either cannabinoid or opiate receptors indicate that these receptors are linked via G proteins to the production of cAMP. Certain studies have also indicated that there may be some interaction between cannabinoid binding sites and opiate receptors in the reward pathway. In addition, there is increasing evidence that cannabinoids interact with opiate systems involved in the perception of pain. In fact, cannabinoids clearly produce analgesic effects in both experimental animals and humans, and of all the potential clinical uses of cannabinoids, the mediation of analgesia has received the most attention. Some evidence also indicates that the cannabinoid receptor system is an analgesic system. 

Sigma receptor ligands bind to metabotropic GPCRs as well as ionotropic cr-Rs (Chapter 3). Endogenous ligands for cr-Rs include some opiates. Sigma-R activation can have antitussive, anxiolytic and ulceroprotective effects. Hypericin from Hypericum perforatum (St John s wort) is... 

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