9 results
Search Results
Now showing 1 - 9 of 9
Publication Metadata only The existence of opioid receptors in the cochlea of guinea pigs(2006-05-01) Nopporn Jongkamonwiwat; Pansiri Phansuwan-Pujito; Stefano O. Casalotti; Andrew Forge; Hilary Dodson; Piyarat Govitrapong; The Institute of Science and Technology for Research and Development, Mahidol University; Srinakharinwirot University; UCL; Mahidol Universityof opioid fibers remains to be investigated. In the present study the expression of opioid receptors and their peptides is demonstrated in young adult guinea pig cochlea. Opioid receptors are mainly expressed in hair cells of the organ of Corti and in inner... and outer spiral bundles with different characteristics for each type of receptor. Co-localization studies were employed to compare the distribution of mu-, delta- and kappa-opioid receptors and their respective peptides, β-endorphin, leu-enkephalinPublication Metadata only Melatonin exerts its analgesic actions not by binding to opioid receptor subtypes but by increasing the release of β-endorphin an endogenous opioid(2005-01-30) Shaik Shavali; Begonia Ho; Piyarat Govitrapong; Saiphon Sawlom; Amornpan Ajjimaporn; Sirirat Klongpanichapak; Manuchair Ebadi; UND School of Medicine & Health Sciences - Northeast Campus; Mahidol University-induced analgesia is blocked by naloxone or pinealectomy. By using selective radioligands [3H]-DAMGO, [3H]-DPDPE, [3-U69593, and 3H]-nociceptin, we have shown that the bovine pinealocytes contain delta and mu, but not kappa or ORL1 opioid receptor subtypes.... In the present study, by using melatonin receptor agonists (6-chloromelatonin or 2-iodo-N-butanoyl-5- methoxytryptamine) or melatonin receptor antagonist (2-phenylmelatonin), we have shown that these agents do not compete with opioid receptor subtypes. HoweverPublication Metadata only Alteration of lymphocyte opioid receptors in methadone maintenance subjects(2010-01-01) Tipa Toskulkao; Ruchee Pornchai; Varaporn Akkarapatumwong; Smith Vatanatunyakum; Piyarat Govitrapong; Mahidol University; Thanyarak hospitalof opiates with lymphocyte opioid receptors. In order to test this hypothesis, the levels of opioid receptors on immune cells obtained from heroin users were determined using saturation binding, and it was found that former heroin addicts on methadone... maintenance treatment had a significantly reduced maximum number (Bmax) of [3H]naloxone binding. The Bmaxvalues were 51.3±7.6fmol/mg protein for the non-addicted group and 25.3±3.1fmol/mg protein for the methadone maintenance group. Opioid receptor genePublication Metadata only The presence of opioid receptors in rat inner ear(2003-01-01) Nopporn Jongkamonwiwat; Pansiri Phansuwan-Pujito; Puangkeaw Sarapoke; Banthit Chetsawang; Stefano O. Casalotti; Andrew Forge; Hilary Dodson; Piyarat Govitrapong; The Institute of Science and Technology for Research and Development, Mahidol University; Srinakharinwirot University; UCLOpioid peptides have been identified in the inner ear but relatively little information is available about the expression and distribution of their receptors. The aim of the present study was therefore to identify and localize the μ (MOR), δ (DOR...) and κ (KOR) opioid receptor subtypes within the rat cochlea. The expression of these opioid receptor subtypes was determined by reverse transcriptase-polymerase chain reaction followed by nested polymerase chain reaction analysis. Amplification of RNAsPublication Metadata only The opioid receptors in inner ear of different stages of postnatal rats(2003-01-01) Pansiri Phansuwan-Pujito; Ladda Saleema; Sujira Mukda; Walaiporn Tongjaroenbuangam; Nuanchan Jutapakdeegul; Stefano O. Casalotti; Andrew Forge; Hilary Dodson; Piyarat Govitrapong; Srinakharinwirot University; The Institute of Science and Technology for Research and Development, Mahidol University; UCLThere is increasing evidence that the opioid system has a role in hearing. To provide further evidence for such a role, the expression of opioid receptor mRNAs and proteins in the inner ear of rats was studied during development from birth (P0...) to postnatal day 16 (P16). A semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to detect changes in the expression of delta- (DOR) kappa- (KOR) and mu- (MOR) opioid receptor mRNAs in rat cochleae at P0, P4, P8 and P16Publication Metadata only The presence of delta and mu-, but not kappa or ORL1receptors in bovine pinealocytes(2002-09-27) Piyarat Govitrapong; Saiphon Sawlom; Manuchair Ebadi; University of North Dakota; The Institute of Science and Technology for Research and Development, Mahidol Universityto identify and characterize the nature and types of opioid receptor in bovine pinealocyte membranes, using a radioligand binding technique with the selective radioligands [3H]DAMGO, [3H]DPDPE, [3H]U69593 and [3H]orphanin-FQ (OFQ) for identifying mu (μ...)-, delta (δ)-, kappa (κ)- and opioid receptor-like (ORL1) receptors, respectively. The saturation experiments on bovine pinealocyte membranes for [3H]DPDPE binding provided Bmaxand Kdvalues of 553±24 fmol/mg protein and 1.3±0.6 nM; and for [3H]DAMGO bindingPublication Metadata only Relationship of opioid receptors with GABAergic neurons in the rat inferior colliculus(2006-10-01) W. Tongjaroenbuangam; N. Jongkamonwiwat; P. Phansuwan-Pujito; S. O. Casalotti; A. Forge; H. Dodson; P. Govitrapong; The Institute of Science and Technology for Research and Development, Mahidol University; Srinakharinwirot University; UCL; Mahidol Universityreported in the inferior colliculus, including opioid peptides. In the present study, the relative distribution of each type of opioid receptor, mu (MOR), delta (DOR) and kappa (KOR) within GABAergic neurons in the inferior colliculus was examined. GABA... immunoreactivity was expressed by small, medium and large neurons and distributed in the central nucleus and the pericentral nucleus of the inferior colliculus. Immunostaining for MOR, DOR and KOR receptors was found in both disc-shaped cells and stellate cellsPublication Metadata only Opioid modulation of GABA release in the rat inferior colliculus(2004-09-07) Walaiporn Tongjaroenbungam; Nopporn Jongkamonwiwat; Joanna Cunningham; Pansiri Phansuwan-Pujito; Hilary C. Dodson; Andrew Forge; Piyarat Govitrapong; Stefano O. Casalotti; Mahidol University; King's College London; Srinakharinwirot University; UCLindicating that μ rather than δ or κ opioid receptors mediate this action. [3H]GABA release was diminished by 16%, and this was not altered by the protein kinase C inhibitor bisindolylmaleimide I. Immunostaining of inferior colliculus cryosections shows... extensive staining for glutamic acid decarboxylase, more limited staining for μ opiate receptors and relatively few neurons co-stained for both proteins. Conclusion: The results suggest that μ-opioid receptor ligands can modify neurotransmitter release in aPublication Metadata only Stimulatory effect of morphine on rat pineal melatonin synthesis via a cyclic AMP-dependent transcription pathway(2005-11-25) Banthit Chetsawang; Piyarat Govitrapong; The Institute of Science and Technology for Research and Development, Mahidol University; Mahidol UniversityThe expression of mRNA of opioid receptors and the existence of opioid binding site in the rat pineal gland have been demonstrated previously. A major finding was that morphine enhanced the activity of the rate-limiting enzyme, N-acetyltransferase