Opioid peptides synthetic

Several additional useful publications demonstrating practical applications of CE/MS methods for neurotransmitter analysis and neuropharmaceutical studies are those of Larsson and Lutz (2000) (neuropeptides including substance P) Hettiarachchi et al. (2001) (synthetic opioid peptides) Varesio et al. (2002) (amyloid-beta peptide) Zamfir and Peter-Katalinic (2004) (gangliosides) Peterson et al. (2002) (catecholamines and metanephrines) Cherkaoui and Veuthey (2002) (fluoxetine) and Smyth and Brooks (2004) (various lower molecular weight molecules including benzodiazepines, steroids, and cannabinols). 

A series of peptides, occurring naturally in brain and possessing pharmacological properties similar to those of morphine, have been described. At least three separate families of peptides have opioid properties (Table 24.2), and the different classes of peptides reside in separate distinct neurons. It is likely that the endogenous opioid peptides coexist in neurons with other nonopioid neurotransmitters. The initial hope that these endogenous agents or synthetic derivatives of them would be found to retain the analgesic activity of the opioids but be devoid of respiratory depression and/or addictive properties has now somewhat abated. 

The third group consists of naturally occurring and synthetic peptides with opioid-like properties. The opioid peptides were discovered during the search for endogenous ligands of the opioid receptors and share the same action and side-effect profile as the non-peptidic compounds... 

While morphine as a component of opium has been in use for centuries and the first synthetic opioid, pethidin, was prepared as early as 1939, opioid peptides, the endogenous pentapeptides Met- and Leu-enkephalin (YGGFM and YGGFL), were identified in brain extracts only in 1975 by Kosterlitz and Waterfield (Hughes et al., 1975 also see Cox et al., 1975 Hughes, 1975 Lord et al., 1977). 

Lottspeich, F., Henschen, A., Brantl, V., and Teschemacher, H. 1980. Novel opioid peptides derived from casein (fj-casomorphins). III. Synthetic peptides corresponding to components from bovine casein peptone. Hoppe-Seyler s Z Physiol. Chem. 361, 1835—1839. 

Boyce R, Li G, Nestler HP, Suenaga T, Still W Clark, Peptidosteroidal receptors for opioid peptides. Sequence-selective binding using a synthetic receptor library, J. Am. Chem. Soc., 116 7955-7956, 1994. 

It is evident that /3-LPT is not the sole source of endogenous opioid peptides found in the pituitary gland now that dynorphin, an active peptide isolated from this organ as early as 1975, has been characterized.(127) This peptide differs from the /3-endorphins (lower mol wt, more basic, more persistent effect in GPI assay, and resistant to CNBr) and its first 13 residues (established by a microsequencing technique) commence with Leu-enkephalin at the N-terminal. The absence of Met5 accounts for its insensitivity toward CNBr. The synthetic tridecapeptide (12, dynorphin 1-13) and dynorphin itself... 

Effects of endogenous opioid peptides and their synthetic analogs on anterior pituitary function... 

The effects of synthetic and natural opioid peptides in isolated organs Ronai, A. Z. Berzetei, I. Szekely, J. I. Bajusz, S. 

The actions listed for antagonists are seen with the antagonist alone. All the correlations in this table are based on studies in rats and mice, which occasionally show species differences. Thus, any extensions of these associations to humans are tentative. Clinical studies do indicate that (x receptors elicit analgesia spinally and supraspinally. Preliminary work with a synthetic opioid peptide, [D-Ala, D-Leu ]enkephalin, suggests that intrathecal 8 agonists are analgesic in humans. 

The opioid peptides isolated from mammalian tissue are known collectively as endorphins, a word that is derived from a combination of endogenous and morphine. The opioid alkaloids and all of the synthetic opioid derivatives are exogenous opioids. Interestingly, the isolation of morphine and codeine in small amounts has been reported from mammalian brain (9). The functional significance of endogenous morphine remains unknown. 

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