Opiate hormone

In the anterior pituitary gland (see Hormones, anteriorpituitaryhormones), both adrenocorticotropic hormones (ACTH) and the endogenous opiate hormone, P-endorphin, are synthesized from a common prohormone (2) (see Opioids,endogenous). In the adrenal medulla, five to seven copies of another opiate hormone, methionine—enkephalin (Met-enkephalin), and one copy of leucine—enkephalin (Leu-enkephalin) are synthesized from each precursor molecule (3). 

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. 

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). 

At the time of the discovery of Met-enkephalin, its sequence was observed to be identical to that of residues 61—65 contained in the C-fragment of the pituitary hormone p-Hpotropin [12584-99-5] (p-LPH) (see Hormones), first isolated in 1964 (11). In 1976, the isolation of a larger peptide fragment, P-endorphin [60617-12-1] that also displayed opiate-like activity was reported (12). This peptide s 31-amino-acid sequence comprised residues 61—91 of P-LPH. Subsequentiy, another potent opioid peptide, dynorphin [72957-38-17, was isolated from pituitary (13). The first five amino acids (qv) of this 17-amino-acid peptide are identical to the Leu-enkephalin sequence (see Table 1). 

In the trans Golgi compartment the peptide is sorted via secretory vesicles into a regulated pathway. In contrast to vesicles of the constitutive pathway, vesicles of the regulated pathway are stored in the cytoplasm until their stimulated release. Membrane depolarisation as well as a wide range of substances such as intracellular mediators, neuropeptides, neurotransmitters, classical hormones, cytokines, growth factors, ions and nutrients induce somatostatin secretion. General inhibitors of somatostatin release are opiates, GABA, leptin and TGF- 3. 

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... 

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). 

FIGURE 1 8-5 Tissue-specific processing of the pro-opiomelanocortin (POMC) precursor yields a wide array of bioactive peptide products. Processing of the POMC precursor varies in various tissues. In anterior pituitary, adrenocorticotropic hormone (ACTH (1-39)) and P-1 ipo tropin (P-LPH) are the primary products of post-translational processing. Arcuate neurons produce the potent opiate P-endorphin (P-endo (1-31)) as well as ACTIK1 -13) NIT,. Intermediate pituitary produces a-melanocyte-stimulating hormone (aMSH), acetylated P endof 1 31) and P-endo(l-27). NTS, nucleus tractus solitarius. 

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. 

The present review will focus on the behavioral consequences of two peptidergic compounds, oxytocin and vasopressin. A variety of other peptides, such as corticotropin releasing hormone (CRH), gonadotropin-hormone releasing hormone (GNRH), and the endogenous opiates, such as beta-endorphin (to name only a few) also influence behavior. 

Experts say that the water supply remains safe, but the buildup of hormones and opiates might cause long-term harm for animals and people. By affecting the environment and water supply, the increasing use of prescription drugs has consequences even for the people and animals not taking drugs. 

How does aspirin differ from morphine Aspirin has three main beneficial effects in your body. It blocks pain in the mild-to-moderate range, and it reduces both inflammation and fever. Its effects on pain derive from its actions not on neuropeptides, such as the endogenous opiates in the brain, but on a local hormone called prostaglandin that is released at the site of bodily pain. When a cell in your body is damaged or injured, prota-glandins are rapidly synthesized and released from the injured cells. Prostaglandins help mediate pain in the injured areas. They sensitize your pain-sensing neurons to mechanical stimulation,... 

OPIOID A drug, hormone, or other chemical substance having sedative or narcotic effects similar to those containing opium or its derivatives a natural brain opiate. 

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