Summary: One of the three major groups of endogenous opioid peptides. They are large peptides derived from the PRO-OPIOMELANOCORTIN precursor. The known members of this group are alpha-, beta-, and gamma-endorphin. The term endorphin is also sometimes used to refer to all opioid peptides, but the narrower sense is used here; OPIOID PEPTIDES is used for the broader group.

Top Publications

  1. Chen Z, Chang M, Peng Y, Zhao L, Zhan Y, Wang L, et al. Osteogenic growth peptide C-terminal pentapeptide [OGP(10-14)] acts on rat bone marrow mesenchymal stem cells to promote differentiation to osteoblasts and to inhibit differentiation to adipocytes. Regul Pept. 2007;142:16-23 pubmed
    ..These observations suggest that commitment of MSCs into osteogenic or adipogenic lineages is regulated by OGP(10-14). ..
  2. Gustafsson L, Oreland S, Hoffmann P, Nylander I. The impact of postnatal environment on opioid peptides in young and adult male Wistar rats. Neuropeptides. 2008;42:177-91 pubmed
    ..By describing effects on opioid peptides, the study addresses the possible role of a deranged endogenous opioid system in the previously described behavioral consequences of MS. ..
  3. Fazzi R, Pacini S, Testi R, Azzarà A, Galimberti S, Testi C, et al. Carboxy-terminal fragment of osteogenic growth peptide in vitro increases bone marrow cell density in idiopathic myelofibrosis. Br J Haematol. 2003;121:76-85 pubmed
    ..These findings suggest that a deficiency of osteoblast-related factors may play a role in bone marrow failure in IMF. ..
  4. Gianoulakis C. Endogenous opioids and addiction to alcohol and other drugs of abuse. Curr Top Med Chem. 2004;4:39-50 pubmed
    ..Furthermore, the use of opioid antagonists in the treatment of drug addiction will be discussed. Special emphasis will be given to ethanol addiction, the drug mainly studied in my laboratory. ..
  5. Oswald L, Wand G. Opioids and alcoholism. Physiol Behav. 2004;81:339-58 pubmed
    ..This paper summarizes both the progress that has been made and the gaps that remain in our understanding of the interactions between the endogenous opioid system and risk for alcoholism. ..
  6. Machuqueiro M, Baptista A. The pH-dependent conformational states of kyotorphin: a constant-pH molecular dynamics study. Biophys J. 2007;92:1836-45 pubmed
    ..These results suggest that there may be strong similarities between the kyotorphin receptor and the structural family of opioid receptors. ..
  7. Li Y, Lefever M, Muthu D, Bidlack J, Bilsky E, Polt R. Opioid glycopeptide analgesics derived from endogenous enkephalins and endorphins. Future Med Chem. 2012;4:205-26 pubmed publisher
    ..Extremely potent and selective opiate agonists have been developed from endogenous peptides, some of which show great promise as drug candidates. ..
  8. Zhang W, Miao J, Ma C, Han D, Zhang Y. ?-Casomorphin-7 attenuates the development of nephropathy in type I diabetes via inhibition of epithelial-mesenchymal transition of renal tubular epithelial cells. Peptides. 2012;36:186-91 pubmed publisher
    ..This protective effect may be associated, in part, with down regulation of epithelial-mesenchymal transition of renal tubular epithelial cells...
  9. Nylander I, Stenfors C, Tan No K, Mathe A, Terenius L. A comparison between microwave irradiation and decapitation: basal levels of dynorphin and enkephalin and the effect of chronic morphine treatment on dynorphin peptides. Neuropeptides. 1997;31:357-65 pubmed

More Information

Publications103 found, 100 shown here

  1. Fazzi R, Galimberti S, Testi R, Pacini S, Trasciatti S, Rosini S, et al. Bone and bone marrow interactions: hematological activity of osteoblastic growth peptide (OGP)-derived carboxy-terminal pentapeptide. II. Action on human hematopoietic stem cells. Leuk Res. 2002;26:839-48 pubmed
  2. Wilkinson C. Roles of acetylation and other post-translational modifications in melanocortin function and interactions with endorphins. Peptides. 2006;27:453-71 pubmed
    ..3) state- and stimulus-dependent effects on the proportional distribution of forms of melanocortins and endorphins; (4) divergent effects of alpha-MSH and beta-endorphin administration; (5) potential roles of beta- and gamma-..
  3. Gustafsson L, Zhou Q, Nylander I. Ethanol-induced effects on opioid peptides in adult male Wistar rats are dependent on early environmental factors. Neuroscience. 2007;146:1137-49 pubmed
    ..The altered sensitivity of the opioid peptides to ethanol may contribute to the previously reported differences in ethanol intake between MS15 and MS360 rats. ..
  4. Chen Z, Chang M, Peng Y, Zhao L, Zhan Y, Wang L, et al. Regulation of endochondral ossification by osteogenic growth peptide C-terminal pentapeptide [OGP(10-14)]. Protein Pept Lett. 2009;16:1074-80 pubmed
    ..We conclude that OGP(10-14) accelerates bone growth. ..
  5. Arima T, Kitamura Y, Nishiya T, Taniguchi T, Takagi H, Nomura Y. Effects of kyotorphin (L-tyrosyl-L-arginine) ON[3H]NG-nitro-L-arginine binding to neuronal nitric oxide synthase in rat brain. Neurochem Int. 1997;30:605-11 pubmed
    ..These results suggest that kyotorphin is degraded to L-Arg by KTPases, which in turn may act as substrate for nNOS. ..
  6. Ploj K, Roman E, Nylander I. Long-term effects of short and long periods of maternal separation on brain opioid peptide levels in male Wistar rats. Neuropeptides. 2003;37:149-56 pubmed
    ..Together, these findings show that repeated periods of MS early in life in male Wistar rats affect the development of the ultrasonic call response and induce long-lasting and possibly permanent alterations in the opioid peptide systems. ..
  7. Lopes S, Soares C, Baptista A, Goormaghtigh E, Cabral B, Castanho M. Conformational and orientational guidance of the analgesic dipeptide kyotorphin induced by lipidic membranes: putative correlation toward receptor docking. J Phys Chem B. 2006;110:3385-94 pubmed
    ..The acylated kyotorphin derivative mimics kyotorphin properties and represents a promising way for entrapment in a drug carrier and transport across the blood-brain barrier. ..
  8. Spreafico A, Frediani B, Capperucci C, Leonini A, Gambera D, Ferrata P, et al. Osteogenic growth peptide effects on primary human osteoblast cultures: potential relevance for the treatment of glucocorticoid-induced osteoporosis. J Cell Biochem. 2006;98:1007-20 pubmed
    ..Our results support the employment of OGP (10-14) in clinical trials addressed to the treatment of different bone remodeling alterations including the GC-induced osteoporosis. ..
  9. Yin H, Miao J, Zhang Y. Protective effect of beta-casomorphin-7 on type 1 diabetes rats induced with streptozotocin. Peptides. 2010;31:1725-9 pubmed publisher
    ..Thus, the results of the present study suggest that beta-casomorphin-7 can protect rats from hyperglycemia and free radical-mediated oxidative stress in diabetic rats. ..
  10. Meisel H, Fitzgerald R. Opioid peptides encrypted in intact milk protein sequences. Br J Nutr. 2000;84 Suppl 1:S27-31 pubmed
    ..Opioid peptides can interact with subepithelial opioid receptors or specific luminal binding sites in the intestinal tract. Furthermore, they may be absorbed and then reach endogenous opioid receptors. ..
  11. Shen J. Research on the neurophysiological mechanisms of acupuncture: review of selected studies and methodological issues. J Altern Complement Med. 2001;7 Suppl 1:S121-7 pubmed
    ..induce analgesia, but that there are differential effects of low- and high-frequency acupuncture on the types of endorphins released...
  12. Tan No K, Taira A, Nakagawasai O, Niijima F, Demuth H, Silberring J, et al. Differential effects of N-peptidyl-O-acyl hydroxylamines on dynorphin-induced antinociception in the mouse capsaicin test. Neuropeptides. 2005;39:569-73 pubmed
    ..The results suggest that Z-Phe-Phe-NHO-Bz is an inhibitor of cysteine proteases preferring cleavage of dynorphin A, with less specificity towards dynorphin B in the mouse spinal cord. ..
  13. Palm S, Daoura L, Roman E, Nylander I. Effects of rearing conditions on behaviour and endogenous opioids in rats with alcohol access during adolescence. PLoS ONE. 2013;8:e76591 pubmed publisher
    ..The study shows that individual behavioural profiling over time in combination with neurobiological investigations provides means for studies of causality between early-life stress, behaviour and vulnerability to psychiatric disorders. ..
  14. Stratmann G, Sall J, Eger E, Laster M, Bell J, May L, et al. Increasing the duration of isoflurane anesthesia decreases the minimum alveolar anesthetic concentration in 7-day-old but not in 60-day-old rats. Anesth Analg. 2009;109:801-6 pubmed publisher
    ..Both pharmacodynamic and a pharmacokinetic components contribute to the decrease in MAC in 7-day-old rats. Neither endorphins nor sensory desensitization mediate the pharmacodynamic component.
  15. Hiramoto K, Yamate Y, Sato E. The Effects of Ultraviolet Eye Irradiation on Dextran Sodium Sulfate-Induced Ulcerative Colitis in Mice. Photochem Photobiol. 2016;92:728-34 pubmed publisher
    ..These results suggested that UV eye irradiation plays an important role in DSS-induced ulcerative colitis. ..
  16. Araújo I, Chaves H, Pachêco J, Val D, Vieira L, Santos R, et al. Role of central opioid on the antinociceptive effect of sulfated polysaccharide from the red seaweed Solieria filiformis in induced temporomandibular joint pain. Int Immunopharmacol. 2017;44:160-167 pubmed publisher
  17. Mancini A, Bianchi A, Tacchino R, Perrelli M, Milardi D, Gentilella R, et al. Opioid dysregulation after biliopancreatic diversion: effect of naloxone on preprandial and postprandial growth hormone (GH)-releasing hormone-induced GH release in surgically induced weight loss. Metabolism. 2001;50:382-6 pubmed
  18. Huang C, Wang Y, Han J, Wan Y. Characteristics of electroacupuncture-induced analgesia in mice: variation with strain, frequency, intensity and opioid involvement. Brain Res. 2002;945:20-5 pubmed
    ..In conclusion, EA induces reliable, strain-dependent analgesia in mice. The naloxone-reversibility of EA, a measure of whether it is opioid or non-opioid mediated, is dependent upon intensity and frequency. ..
  19. Chernov A, Sergievich L, Karnaukhova N. Analysis of the Effect of β-Endorphin-Like Peptide Pentarphin on Intracellular Ca²⁺ Concentration in Early Mouse Embryos Using Fluorescent Probes. Bull Exp Biol Med. 2015;159:459-62 pubmed publisher
    ..We used fluorescent Ca(2+) indicators Fluo-3 AM and Fura Red AM. Pentarphin added to embryos in a concentration of 0.1 μM 1.5-2 fold increased intercellular Ca(2+) level in comparison with the initial level. ..
  20. Champion H, Bivalacqua T, Zadina J, Kastin A, Kadowitz P. Vasodilator responses to the endomorphin peptides, but not nociceptin/OFQ, are mediated by nitric oxide release. Ann N Y Acad Sci. 1999;897:165-72 pubmed
    ..Moreover, these results demonstrate that responses to these peptides are not mediated by the release of vasodilator prostaglandins or K+ATP channel opening in the hindquarters vascular bed. ..
  21. Zoghbi S, Trompette A, Claustre J, El Homsi M, Garzón J, Jourdan G, et al. beta-Casomorphin-7 regulates the secretion and expression of gastrointestinal mucins through a mu-opioid pathway. Am J Physiol Gastrointest Liver Physiol. 2006;290:G1105-13 pubmed
    ..Because intestinal mucins have a crucial mucosal protective function, dairy products containing beta-casomorphin-7 may improve intestinal protection and could have dietary and health applications. ..
  22. Cieslińska A, Kostyra E, Kostyra H, Oleński K, Fiedorowicz E, Kaminski S. Milk from cows of different ?-casein genotypes as a source of ?-casomorphin-7. Int J Food Sci Nutr. 2012;63:426-30 pubmed publisher
    ..The obtained results suggest a possibility to provide a new nutritional factor for milk quality based on the content of ?-casomorphin-7 liberated in vivo from milk digested by a mixture of the gastrointestinal enzymes. ..
  23. Lodyga Chruscinska E, Brzezinska Blaszczyk E, Micera G, Sanna D, Kozlowski H, Olczak J, et al. Can the 1,5-disubstituted tetrazole ring modify the co-ordinating ability and biological activity of opiate-like peptides?. J Inorg Biochem. 2000;78:283-91 pubmed
    ..The ability of casomorphin tetrazole analogues to activate rat mast cells to histamine release in vitro in the presence of copper(II) has been studied. ..
  24. van Ree J, Niesink R, Van Wolfswinkel L, Ramsey N, Kornet M, Van Furth W, et al. Endogenous opioids and reward. Eur J Pharmacol. 2000;405:89-101 pubmed
    ..It is concluded that endogenous opioids may play a role in the vulnerability to certain diseases, such as addiction and autism, but also when the disease is present, such as alcoholism. ..
  25. Berger K, Winzell M, Mei J, Erlanson Albertsson C. Enterostatin and its target mechanisms during regulation of fat intake. Physiol Behav. 2004;83:623-30 pubmed
    ..We frame a hypothesis that regulation of fat intake through enterostatin contains a reward component, which is an F1-ATPase-mediated pathway, possibly complemented with an opioidergic pathway. ..
  26. Luan Y, Wang D, Yu Q, Chai X. Action of ?-endorphin and nonsteroidal anti-inflammatory drugs, and the possible effects of nonsteroidal anti-inflammatory drugs on ?-endorphin. J Clin Anesth. 2017;37:123-128 pubmed publisher
  27. Sakurada S, Sawai T, Mizoguchi H, Watanabe H, Watanabe C, Yonezawa A, et al. Possible involvement of dynorphin A release via mu1-opioid receptor on supraspinal antinociception of endomorphin-2. Peptides. 2008;29:1554-60 pubmed publisher
  28. Hsu C, Lin M, Cheng J, Wu M. Diosmin, a Citrus Nutrient, Activates Imidazoline Receptors to Alleviate Blood Glucose and Lipids in Type 1-Like Diabetic Rats. Nutrients. 2017;9: pubmed publisher
    ..Taken together, we suggest that diosmin may activate I-2R to enhance the secretion of β-endorphin from adrenal glands and to influence metabolic homeostasis, resulting in alleviation of blood glucose and lipids in STZ-diabetic rats. ..
  29. Epple A, Nibbio B, Spector S, Brinn J. Endogenous codeine: autocrine regulator of catecholamine release from chromaffin cells. Life Sci. 1994;54:695-702 pubmed
    ..It appears that codeine is an autocrine regulator which suppresses CA release via naloxone-insensitive receptors, and stimulates CA release via opiate receptor(s). Co-released morphine may modulate the action of codeine. ..
  30. Sanderson K, Andren P, Caprioli R, Nyberg F. In vitro metabolism of LVV-hemorphin-7 in human plasma studied by reversed-phase high-performance liquid chromatography and micro-electrospray mass spectrometry. J Chromatogr A. 1996;743:207-12 pubmed
    ..Incubations were performed with and without different protease inhibitors. Results showed that LVV-hemorphin-7 was metabolized from the N-terminal end of the peptide, probably by an amastatin-sensitive exopeptidase. ..
  31. Ikeda K, Kobayashi K, Kobayashi T, Ichikawa T, Kumanishi T, Kishida H, et al. Functional coupling of the nociceptin/orphanin FQ receptor with the G-protein-activated K+ (GIRK) channel. Brain Res Mol Brain Res. 1997;45:117-26 pubmed
    ..We conclude that the nociceptin/orphanin FQ receptor couples with the GIRK channel in various neurons, including hippocampal pyramidal cells, thereby modulating neuronal excitability. ..
  32. Mullner K, Gyires K, Furst S. Involvement of the opioid system in the central antisecretory action of alpha-2 adrenoceptor agonists in rat. J Physiol Paris. 2001;95:209-14 pubmed
  33. Bocheva A, Dzambazova Maximova E. Effects of kyotorphin and analogues on nociception and pentylenetetrazole seizures. Folia Med (Plovdiv). 2004;46:40-4 pubmed
    ..Taken together, these results reveal Kyo, Tyr-Cav and Tyr(Cl2)-Cav as a behaviorally active peptide in experimental animal models. ..
  34. Basso L, Boué J, Mahiddine K, Blanpied C, Robiou du Pont S, Vergnolle N, et al. Endogenous analgesia mediated by CD4(+) T lymphocytes is dependent on enkephalins in mice. J Neuroinflammation. 2016;13:132 pubmed publisher
    ..In mice, CD4(+) T lymphocytes completely lose their analgesic opioid-mediated activity when lacking enkephalins. ..
  35. Alves D, Soares A, Francischi J, Castro M, Perez A, Duarte I. Additive antinociceptive effect of the combination of diazoxide, an activator of ATP-sensitive K+ channels, and sodium nitroprusside and dibutyryl-cGMP. Eur J Pharmacol. 2004;489:59-65 pubmed
  36. Wen D, Hu X, Wang Y, Luo J, Lin W, Jia L, et al. Effects of aqueous extracts from Panax ginseng and Hippophae rhamnoides on acute alcohol intoxication: An experimental study using mouse model. J Ethnopharmacol. 2016;192:67-73 pubmed publisher
    ..AEPH can markedly increase the levels of ADH, ALDH, decrease EO activity in liver and decrease the concentration of ?-EP and LENK in the brain to against acute alcohol intoxication in mice. ..
  37. Manninen S, Tuominen L, Dunbar R, Karjalainen T, Hirvonen J, Arponen E, et al. Social Laughter Triggers Endogenous Opioid Release in Humans. J Neurosci. 2017;37:6125-6131 pubmed publisher
    ..Modulation of the opioidergic activity by social laughter may be an important neurochemical mechanism reinforcing and maintaining social bonds between humans. ..
  38. King M, Su W, Chang A, Zuckerman A, Pasternak G. Transport of opioids from the brain to the periphery by P-glycoprotein: peripheral actions of central drugs. Nat Neurosci. 2001;4:268-74 pubmed
    ..This ability of the Pgp transport system to pump functionally active compounds from the brain to periphery defines a potentially important mechanism for the central nervous system to modulate peripheral systems...
  39. Strassburger W, Friderichs E. [Opioid peptides. Ironman, mother's milk and toad's skin]. Pharm Unserer Zeit. 2002;31:52-8 pubmed
  40. Cao Z, Liu L, Van Winkle D. Activation of delta- and kappa-opioid receptors by opioid peptides protects cardiomyocytes via KATP channels. Am J Physiol Heart Circ Physiol. 2003;285:H1032-9 pubmed
    ..7 for HMR-1098 and ME + HMR-1098, respectively (P < 0.01). We conclude that opioid peptide-induced cardioprotection is mediated by delta- and kappa-receptors and involves sarcolemmal and mitochondrial ATP-sensitive K+ channels. ..
  41. Shirayama Y, Ishida H, Iwata M, Hazama G, Kawahara R, Duman R. Stress increases dynorphin immunoreactivity in limbic brain regions and dynorphin antagonism produces antidepressant-like effects. J Neurochem. 2004;90:1258-68 pubmed
    ..These results indicate that both dynorphin A and dynorphin B contribute to the effects of stress, and suggest that blockade of kappa-opioid receptors may have therapeutic potential for the treatment of depression. ..
  42. Csaba G, Kovacs P, Pallinger E. Effect of femtomolar concentrations of hormones on insulin binding by Tetrahymena, as a function of time. Cell Biochem Funct. 2008;26:205-9 pubmed
    ..EGF provoked special behaviour: it increased hormone binding after 30 and 60 min. The results call attention to the extreme sensitivity of Tetrahymena receptors to hormonal inductions and to its quick response ability. ..
  43. Skobowiat C, Postlethwaite A, Slominski A. Skin Exposure to Ultraviolet B Rapidly Activates Systemic Neuroendocrine and Immunosuppressive Responses. Photochem Photobiol. 2017;93:1008-1015 pubmed publisher
    ..Thus, cutaneous exposure to UVB rapidly stimulates systemic CRH, ACTH, ?-endorphin and CORT production accompanied by rapid immunosuppressive effects in splenocytes that appear to be independent of the HPA axis...
  44. Nagy K, Berhes I, Kovacs T, Kavasi N, Somlai J, Kovacs L, et al. Study on endocronological effects of radon speleotherapy on respiratory diseases. Int J Radiat Biol. 2009;85:281-90 pubmed publisher
  45. Plener P, Brunner R, Resch F, Fegert J, Libal G. [Nonsuicidal self-injury in adolescence]. Z Kinder Jugendpsychiatr Psychother. 2010;38:77-88; quiz 88-9 pubmed publisher
    ..There is little evidence for psychopharmacological interventions in childhood and adolescence; thus treatment should focus on psychotherapeutic interventions. ..
  46. Conceição K, Magalhães P, Campos S, Domingues M, Ramu V, Michalek M, et al. The anti-inflammatory action of the analgesic kyotorphin neuropeptide derivatives: insights of a lipid-mediated mechanism. Amino Acids. 2016;48:307-18 pubmed publisher
    ..Accumulation of IbKTP-NH2 in the membrane favors both direct permeation and local interaction with putative receptors as the location of the KTP-NH2 residue of IbKTP-NH2 and free KTP-NH2 in lipid membranes is the same. ..
  47. Ji B, Zhao G, Sakurai R, Cao Y, Zhang Z, Wang D, et al. Effect of Maternal Electroacupuncture on Perinatal Nicotine Exposure-Induced Lung Phenotype in Offspring. Lung. 2016;194:535-46 pubmed publisher
    ..We conclude that EA is a promising novel intervention against the smoke exposed lung damage to the developing lung. ..
  48. Molteno A, Bennett N. Social suppression in nonreproductive female Damaraland mole-rats, Cryptomys damarensis: no apparent role for endogenous opioid peptides. Horm Behav. 2002;41:115-25 pubmed
    ..These results suggest EOPs play a role in sexual function but that socially induced infertility is unlikely to be mediated through the EOP system. ..
  49. Ribeiro S, Kennedy S, Smith Y, Stohler C, Zubieta J. Interface of physical and emotional stress regulation through the endogenous opioid system and mu-opioid receptors. Prog Neuropsychopharmacol Biol Psychiatry. 2005;29:1264-80 pubmed
    ..Possible future areas of study at the interface of "mind" (cognitive-emotional) and "body" (physical) functions are delineated in this context. ..
  50. Kost N, Sokolov O, Kurasova O, Dmitriev A, Tarakanova J, Gabaeva M, et al. Beta-casomorphins-7 in infants on different type of feeding and different levels of psychomotor development. Peptides. 2009;30:1854-60 pubmed publisher
  51. Barg J, Belcheva M, Rowinski J, Coscia C. kappa-Opioid agonist modulation of [3H]thymidine incorporation into DNA: evidence for the involvement of pertussis toxin-sensitive G protein-coupled phosphoinositide turnover. J Neurochem. 1993;60:1505-11 pubmed
    ..In mixed glial cell aggregates, U50488 increased thymidine incorporation into DNA 3.1-fold, and this stimulation was reversed by the opioid antagonist naltrexone. ..
  52. Trujillo K, Bronstein D, Sanchez I, Akil H. Effects of chronic opiate and opioid antagonist treatment on striatal opioid peptides. Brain Res. 1995;698:69-78 pubmed
    ..These studies are consistent with the suggestion that Prodyn neurons may have a role in the consequences of long-term opiate administration. ..
  53. Zadina J, Hackler L, Ge L, Kastin A. A potent and selective endogenous agonist for the mu-opiate receptor. Nature. 1997;386:499-502 pubmed
    ..The new peptides have the highest specificity and affinity for the mu receptor of any endogenous substance so far described and they may be natural ligands for this receptor. ..
  54. Sobiś Glinkowska M, Mikucki J, Lisiecki P. [Animal body iron sources utilized in vitro by enterococci]. Med Dosw Mikrobiol. 2001;53:9-15 pubmed
    ..Spectrum of utilized iron sources was not depended on species affiliation and origin of strains. ..
  55. Pol O, Valle L, Puig M. Antisense oligodeoxynucleotides to mu- and delta-opioid receptor mRNA block the enhanced effects of opioids during intestinal inflammation. Eur J Pharmacol. 2001;428:127-36 pubmed
  56. Homayoun H, Khavandgar S, Dehpour A. The involvement of endogenous opioids and nitricoxidergic pathway in the anticonvulsant effects of foot-shock stress in mice. Epilepsy Res. 2002;49:131-42 pubmed
    ..Taken together, these results show that NO synthesis, through constitutive but not iNOS, is involved in opioid-dependent stress-induced anticonvulsant effects against electrical and PTZ-induced convulsions. ..
  57. Goodman R, Coolen L, Anderson G, Hardy S, Valent M, Connors J, et al. Evidence that dynorphin plays a major role in mediating progesterone negative feedback on gonadotropin-releasing hormone neurons in sheep. Endocrinology. 2004;145:2959-67 pubmed
  58. Capasso A, Loizzo A. Guinea-pigs treated with beta-endorphin fragments DTgammaE and DEgammaE exhibit reduced morphine inhibition of electrically-induced contractions. Prog Neuropsychopharmacol Biol Psychiatry. 2000;24:51-9 pubmed
    ..C. of guinea-pig ileum thus confirming an important functional interaction between gamma-endorphin derivatives and opioid system. ..
  59. Johansson P, Hallberg M, Kindlundh A, Nyberg F. The effect on opioid peptides in the rat brain, after chronic treatment with the anabolic androgenic steroid, nandrolone decanoate. Brain Res Bull. 2000;51:413-8 pubmed
  60. Douglas A, Russell J. Endogenous opioid regulation of oxytocin and ACTH secretion during pregnancy and parturition. Prog Brain Res. 2001;133:67-82 pubmed
    ..So, opioids continue to regulate the activity of oxytocin and hypothalamo-pituitary-adrenal mechanisms in labor; inhibition of oxytocin neurons at this time may control the spacing of pup births. ..
  61. Vrinten D, Gispen W, Kalkman C, Adan R. Interaction between the spinal melanocortin and opioid systems in a rat model of neuropathic pain. Anesthesiology. 2003;99:449-54 pubmed
  62. Battolla B, Bernardini N, Petrini M, Mattii L. The small peptide OGP(10-14) reduces proliferation and induces differentiation of TPO-primed M07-e cells through RhoA/TGFbeta1/SFK pathway. Med Sci Monit. 2011;17:SC1-5 pubmed
    ..OGP(10-14) induces TPO-primed M07-e cells differentiation through RhoA/TGF?1/SFKs signalling pathway. In particular OGP(10-14) acts as a Src inhibitor, showing the same effects of PP2. ..
  63. Kornyei J, Vertes Z, Kovacs K, Gocze P, Vertes M. Developmental changes in the inhibition of cultured rat uterine cell proliferation by opioid peptides. Cell Prolif. 2003;36:151-63 pubmed
    ..Our novel data demonstrate two different phases of the inhibitory action of opioid peptides on rat uterine cell proliferation during ontogeny with an insensitive interval in between. ..
  64. Song B, Marvizón J. N-methyl-D-aspartate receptors and large conductance calcium-sensitive potassium channels inhibit the release of opioid peptides that induce mu-opioid receptor internalization in the rat spinal cord. Neuroscience. 2005;136:549-62 pubmed
    ..Since mu-opioid receptors in the dorsal horn mediate analgesia, inhibition of spinal opioid release could contribute to the hyperalgesic actions of spinal N-methyl-D-aspartate receptors. ..
  65. Csaba G, Kovacs P, Pallinger E. In vitro effect of biogenic amines on the hormone content of immune cells of the peritoneal fluid and thymus. Is there a hormonal network inside the immune system?. Cell Biol Int. 2007;31:224-8 pubmed
    ..Endorphin level was resistant to hormonal treatments. The results call attention to a possible hormonal network inside the immune system in which hormones produced by the immune cells themselves can influence each other. ..
  66. Garcia Larrea L, Peyron R. Motor cortex stimulation for neuropathic pain: From phenomenology to mechanisms. Neuroimage. 2007;37 Suppl 1:S71-9 pubmed
    ..This, along with the delayed and long-lasting activation of several brain structures, is consistent with the clinical effects of MCS, which may also last for hours or days after MCS discontinuation. ..
  67. Zuberi A, Townsend L, Patterson L, Zheng H, Berthoud H. Increased adiposity on normal diet, but decreased susceptibility to diet-induced obesity in mu-opioid receptor-deficient mice. Eur J Pharmacol. 2008;585:14-23 pubmed publisher
    ..Because of the complexity of mu-opioid gene regulation and tissue distribution, more selective and targeted approaches will be necessary to fully understand the underlying mechanisms. ..
  68. Poiana C, Musat M, Carsote M, Chirita C. Premenstrual dysphoric disorder: neuroendocrine interferences. Rev Med Chir Soc Med Nat Iasi. 2009;113:996-1000 pubmed
    ..The heritability of the syndrome is sustained by genetic polymorphism in ESR1 gene. Thus, the PMDD is the result of multiple disturbances regarding neuroendocrine systems. ..
  69. Katsuyama S, Mizoguchi H, Kuwahata H, Komatsu T, Nagaoka K, Nakamura H, et al. Involvement of peripheral cannabinoid and opioid receptors in ?-caryophyllene-induced antinociception. Eur J Pain. 2013;17:664-75 pubmed publisher
    ..pl. BCP is mediated by activation of CB2 receptors, which stimulates the local release from keratinocytes of the endogenous opioid ?-endorphin. The combined injection of morphine and BCP may be an alternative in treating chemogenic pain. ..
  70. Schmitt T, Mousa S, Brack A, Schmidt D, Rittner H, Welte M, et al. Modulation of peripheral endogenous opioid analgesia by central afferent blockade. Anesthesiology. 2003;98:195-202 pubmed
    ..05). These findings suggest an interplay of central and peripheral mechanisms of pain control. An effective central inhibition of pain apparently signals a reduced need for recruitment of opioid-containing immune cells to injured sites. ..
  71. Stefano G, Zhu W, Cadet P, Bilfinger T, Mantione K. Morphine enhances nitric oxide release in the mammalian gastrointestinal tract via the micro(3) opiate receptor subtype: a hormonal role for endogenous morphine. J Physiol Pharmacol. 2004;55:279-88 pubmed
    ..Taken together, we surmise morphine acts as a hormone to limit gut activity via micro(3) coupled to NO release since micro opiate receptors are found in the gut and endogenous morphine is not but is found in blood. ..
  72. McCarthy L, Nitsche J, Pintar J, Rogers T. The delta-opioid receptor participates in T-cell development by promoting negative selection. J Neuroimmunol. 2004;153:91-8 pubmed
    ..These results suggest that delta-opioids may play a homeostatic role in the negative selection process during T-cell development. ..
  73. Dufourny L, Caraty A, Clarke I, Robinson J, Skinner D. Progesterone-receptive beta-endorphin and dynorphin B neurons in the arcuate nucleus project to regions of high gonadotropin-releasing hormone neuron density in the ovine preoptic area. Neuroendocrinology. 2005;81:139-49 pubmed
    ..These data strongly support the hypothesis that progesterone acts in the arcuate nucleus through beta-endorphin and dynorphin B neurons to affect preoptic area GnRH neurons. ..
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