Opiate hormones receptors

Coe, C.L. and Erickson, C., Stress decreases natural killer cell activity in the young monkey even after blockade of steroid and opiate hormone receptors, Dev. Psychobiol., 30, 1, 1997. 

Amino acid receptors Monoamine receptors Lipid receptors Purine receptors Neuropeptide receptors Peptide hormone receptors Chemokine receptors Glycoprotein receptors Protease receptors Metabotropic glutamate and GABAb receptors Adrenoceptors, dopamine and 5-HT receptors, muscarinic and histamine receptors Prostaglandin, thromboxane and PAF receptors Adenosine and ATP (P2Y) receptors Neuropeptide Y, opiate, cholecystokinin VIP, etc. Angiotensin, bradykinin, glucagon, calcitonin, parathyroid, etc. Interleukin-8 TSH, LH/FSH, chorionic gonadotropin, etc. Thrombin... 

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). 

Fragments of the peptide hormone p-lipotropin have been found to show similar binding to opiate receptors. These molecules, the endorphins, show profound CNS activity in experimental animals. It is of interest that one of these, p-endorphin, incorporates in its chain the exact sequence of amino acids that constitutes methionine enkaphalin. 

G.B. Stefano, W. Zhu, P. Cadet, T.V. Bilfinger, and K. Mantione, Morphine enhances nitric oxide release in the mammalian gastrointestinal tract via the mu 3 opiate receptor subtype a hormonal role for endogenous morphine. J. Physiol. Pharmacol. 55, 279-288 (2004). 

Membrane-associated receptors are linked to transducing proteins (like G-proteins) in the inner portion of the membrane. G-protein coupled receptor (GPCR) families comprise a major class of the receptors that are pharmacologically relevant, such as muscarinic acetyl choline receptors, adrenoceptors, dopamine receptors, serotonine, opiate, peptide hormone, purinerg receptors, and also sensory chemoreceptors. A large variety of subtypes are described in the pharmacological literature. 

Additional mediators of gastric acid secretion include calcium, gastrin-releasing hormone and enkephalin, while opiate receptors have also been identified on parietal cells. 

I n analogy to other- better u nderstood - receptor systems like some hormone and opiate receptors it is generally accepted that the olfacto receptors are proteins, and there are some facts known that support this hypothesis. One of these arguments is that, sometimes, slight modification of the chemical structure of a stimulus molecule can lead to big changes in the odor impression this might be qualitative or quantitative. 

It has been speculated that classical hormonal feedback mechanisms might act to suppress endogenous opioid synthesis when the receptors are occupied by an endogenous opiate-like morphine.61 Enkephalin levels in the brain of morphine-tolerant rats are increased, 1 and there is cross-toler-ance between morphine and Met-enkephalin.62... 

There are many small oligopeptides that serve as neurotransmitters and hormones. The enkephalins, endorphins, etc. have already ben mentioned in the section on opiate receptors. Two amino acids that serve in this way are glycine, an inhibitory transmitter, and glutamic acid, an excitatory transmitter. gamma-Aminobutyric acid (GABA) is less well established, but probably an inhibitory transmitter. Peptide hormones like vasopressin and somatostatin are made in the pituitary gland or hypothalamus and influence processes elsewhere in the body. 

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