• Archives of Pharmacal Research
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• v.18 no.2
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• pp.113-117
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• 1995

We re-cloned mouse ${\delt}-Opioid$receptor from NG108-15 cells using RT-PCR, and confirmed it by restriction analysis and by sequencing the beginning and end part of the amplified DNA. When transiently expressed in COS-7 cells, cloned ${\delt}-Opioid$ receptor showed saturable and specific binding to $[^3H]$naloxone with very similar binding parameters to originally reported ones. To make antibodies specific for the ${\delt}-Opioid$ receptor, the carboxy tail of the receptor, which is unique to the ${\delt}-Opioid$ receptor compared with other opioid receptors, was expressed in bacteria as a ufsion proteinwith glutathione S-transferase. Purified fusion protein selective for ${\delt}-Opioid$ receptor when tested by western blotting using membrane proteins prepared from transfected COS-7 cells. Cloned ${\delt}-Opioid$ receptor andl antibodies specific for ${\delt}-Opioid$ receptor are going to be valuable tools for studying pharmacological actions of the ${\delt}-Opioid$ receptor and morphine dependence.

• The Korean Journal of Pharmacology
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• v.30 no.3
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• pp.291-297
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• 1994

Our purpose was to gain insight into a possible modulatory role for ${\mu},\;{\delta},\;and\;{\kappa}$ opioid receptors by neuroleptics (chlorpromazine, thioridazine, haloperidol, sulpiride, and pimozide) in chronic morphine 5 mg/kg and 20 mg/kg treated mouse striatum. We attempted quantitative receptor assays using highly specific radioligands, $[^3H]\;DAGO\;([D-Ala^2,\;N-Mephe^4,\;Glycol^5]\;enkephalin)$, $[^3H]DPDPE\;([D-Pen^2,\;D-Pen^5]\;enkephalin)$ and $[^3H]\;DPN(diprenorphine)$ to measure the binding affinity in the experimental groups. The decrease of $[^3H]DAGO$ binding was potentiated by sulpiride and pimozide in the chronic morphine treatment (5 mg/kg and 20 mg/kg). The decrease of $[^3H]DPDPE$ binding was inhibited by chlorpromazine, thioridazine, haloperidol, sulpiride, and pimozide in chronic morphine treatment (5 mg/kg and 20 mg/kg). The decrease of $[^3H]\;DPN$ binding was significantly inhibited by chlorpromazine, thioridazine, sulpiride, and pimozide in chronic morphine 20 mg/kg treatment. $[^3H]\;DPN$ binding on the neuroleptics was antagonized by naloxone pretreatment in chronic morphine 20 mg/kg treatment. These findings suggest that neuroleptics influence opposing tonically active on the ${\delta},\;and\;{\kappa}$ opioid receptor compared with ${\mu}$ opioid receptor in the chronic morphine treated mouse striatum.

• Biomolecules & Therapeutics
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• v.7 no.3
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• pp.278-284
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• 1999

DK1001 is a thebain derivative, which is newly synthesized as an alkaloid analgesic. This study was designed to study effects of DK1001 on the ligands binding to the opioid receptor subtypes, and general pharmacology of DK1001. DK1001 inhibited the binding of [$^3H$]DAMGO, a selective mu-subtype agonist, to the opioid receptor of rat forebrain in a concentration-dependent manner. $EC_{50}$ of DK1001 was significantly lower than that of morphine. DK1001 inhibited the binding of 〔$^3$H〕DPDPE, a selective delta-subtype agonist concentration-dependently. DK1001(0.5 mg/kg) had no effects on behavior, body temperature, blood pressure. respiratory rate, and intestinal charcoal propulsion of mice. In addition, DK1001 did not affect on the contractilities of isolated muscle strips of aorta, ileum, and trachea of rats. These results suggest that DK1001 might be a potent analgesic without serious side effects.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.219-224
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• 1995

The modulatory effects of total ginseng saponin (TGS) on the 1, 6, and opioid receptor binding in morphine tolerance and dependence were examined in this study. The specific [$^{3}H$]DAGO ([D-$Ala^2$, N-$Mephe^4$, $Glyco^4$] enkephalin) binding was significantly increased in chronic morphine (10 mg/kg, i.p.) treated mouse striatum. The specific [$^{3}H$]DPDPE ([D-$Pen^2$, D-$Pen^5$] enkephalin) binding was ignificantly increased following morphine treatment in the mouse striatum and cortex. Also, an apparent decrease in the affinity of [$^{3}H$]DPN (diprenorphine) was observed after chronic morphine treatment in mouse striatum and cortex. 7GS produced a sleight increase of specific [$^{3}H$]DAGO, [$^{3}H$]DPDPE binding and a significant increase of specific [$^{3}H$]DPN binding in the mouse brain striatum. In cortex, TGS produced an inhibition of specific [$^{3}H$]DAGO and [$^{3}H$]DPDPE binding and increase of the specific [$^{3}H$]DPN binding. The prolonged administration of TGS (25, 50, 100, and 150 mg/kg, i.p., 3 wks) produced an inhibition of increased [$^{3}H$]DAGO specific binding following morphine without significant changes in the agonist binding to and receptors in mouse striatum and cortex. These contracted alterations in $\mu$, $\gamma$ and $\kappa$ opiate receptor binding were dependent in TGS dogs and brain sites.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.305-305
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• 1994

It has been shown that there are several subtypes of $\kappa$ opioid receptor, We have evaluated the properties of non-${\mu}$, non-$\delta$ binding of 〔$^3$H〕DIP, a nonselective opioid antagonist, in rat cortex membranes. Binding to ${\mu}$ and $\delta$ sites was inhibited by the use of an excess of competing selective agonists (DAMGO, DPDPE) for these sites. (-)Ethylketocyclazocine(EKC) inhibited 〔$^3$H〕DIP binding with Ki. of 70 nM. However, arylacetamides (U69593 and U50488H) gave little inhibition. Also, we have examined the opioid modulation of K$\^$+/(30 mM)-induced histamine release in rat frontal cortex slices labeled with 1-〔$^3$H〕histidine. The 〔$^3$H〕histamine release from cortex slices was inhibited by EKC, a $\kappa$$_1$-and $\kappa$$_2$-agonist, in a concentration-dependent manner(10 to 10,000 nM). The IC$\sub$50/ of EKC was 107 ${\pm}$ 6 nM. However, the $\delta$ receptor selective agonists, DPDPE and deltorphine II, ${\mu}$ receptor agonists, DAMGO and TAPS, $\kappa$$_1$-agonists, U69593 and U50488H, and $\varepsilon$-agonist, ${\beta}$-endorphin, did not inhibit histamine release even in micromoiar dose, indicating that ${\mu}$, $\delta$ or $\kappa$$_1$ receptors are not involved. The concentration-response curve of EKC was shifted to right in the presence of naloxone (300 nM), a ${\mu}$ preferential antagonist, norbinaltorphimine(300 nM), a $\kappa$$_1$ preferential antagonist and bremazocine(1 nM), a $\kappa$$_1$-agonist and $\kappa$$_2$-antagonist. These results suggest that $\kappa$$_2$ opioid receptor regulates histamine release in the frontal cortex of the rat.

• Journal of Nutrition and Health
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• v.17 no.4
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• pp.313-319
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• 1984

The effect of morphine on food intake on freely fed Sprague - Dawley rats was examined Opiate receptor binding assay was used to investigate the possibility of the opioid system involved in food intake regulation of normal rats. When rats were treated with 5mg morphine per kg body weight, subcutaneously, the food intake of the rats for the first 2 hours was increased 125% of the control rats. The effect of morphine on food intake of male and female rats were greater when the morphine was injected at 10 : 00 a.m than that in the rats administered the morphine at 4 : 00 p.m. The morphine effect was not significant in older rats and female was more responsive than male rats. In morphine treated rats, opioid receptor density has exhibited 33% reduction as measured by the $^{3}H-naloxone$ binding assay with whole brain homogenate. These results indicate that the increase of food intake by morphine for 2 hours after the injection may be mediated through the opioid system in rat brain.

• The Korean Journal of Pharmacology
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• v.30 no.2
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• pp.153-165
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• 1994

In this study, we tested the influences of several ${\kappa}$ opioid ligands on the $[^3H]diprenorphine$ binding in rat and guinea pig cortex membrane preparations. Using paradigm to block ${\mu}\;and\;{\delta}$ opioid receptors with $DAMGO(1{\mu}M)$ and $DPDPE(1{\mu}M)$, $[^3H]diprenorphine$ labeled ${\kappa}$ sites. Competition analysis in both rat and guinea pig cortex has shown a single population of $[^3H]diprenorphine$ binding site with different Kd values, respectively. There is a significant difference in Ki values of (-) WIN44441 and (+)WIN44441 in both rat and guinea pig cortex. Bremazocine, (-)ethylketocyclazocine, (-)cyclazocine, nor-binaltorphimine effectively inhibited the $[^3H]diprenorphine$ binding with different Ki values in rat and guinea pig cortex. U-69,593, U-50,488H and dynorphine-A (1-8) did not inhibit the $[^3H]diprenorphine$ binding in rat but in guinea pig cortex. Nor-binaltorphimine was a ligand discriminate the ${\kappa}_1$, and ${\kappa}_2$ receptor most effectively. We, also, examined the influence of Na ion and $GTP{\gamma}S$, a nonhydrolyzable guanine nucleotide analog, on the inhibition of $[^3H]diprenorphine$ binding by diprenorphine, (-)ethyl-ketocyclazocine, U-69,593 and bremazocine. By the replacement of NaCl with N-methy-D-glucamine or addition of $GTP{\gamma}S$, Ki values of diprenorpnine were not changed and that of ethylketocyclazocine were changed significantly in both rat and guinea pig cortex. The Ki value of bremazocine was decreased by removal of Na ion, and increased by $GTP{\gamma}S$, however, was not changed by any one of either. These results suggest that there are 2 kinds of subtypes of ${\kappa}$ opioid receptor, ${\kappa}_1$, and ${\kappa}_2$, showing different Ki values for various ${\kappa}$ opioid ligands, also, bremazocine possess the antagonistic property at ${\kappa}_2$ site which is dominant subtype of K receptor in rat cortex.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.1-6
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• 1999

Effects of Panax ginseng on the morphine toxicity were studied in relation to its effects on the opioid receptor-G protein interactions. Morphine treatments (3 days) reduced the body weight increment rate and the weight of the thymus and spleen. These changes were usually recovered by the concomitant administration of ginseng total saponin (GTS) but occasionally further deteriorated. This discrepancy was studied in relation to the opioid receptor coupling to G protein, that is, the effects of morphine and GTS on the opioid receptors were studied using the antagonist-agonist competitive binding studies. When GTS recovered the morphine toxicity, morphine shifted the striatal $\delta$ receptors to slightly higher affinity state, and this was partly recovered by the GTS treatment. However, morphine did not have any effect on the affinity state of $\delta$ receptor from NG108-15 cells, suggesting that additional factors were needed for the modulation of the affinity states of $\delta$ receptor. Effects of morphine and GTS on $\mu$ receptor were complicate and variable, and we could not reach a clear conclusion. The morphine toxicity might accompany complicate biological involvements, and the modulation of the affinity states of the opioid receptors might explain a part of the effects of GTS on the morphine toxicity.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.1-9
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• 1994

It has been shown that there are several subtypes of ${\kappa}$ opioid receptor. We examined ligand binding profiles and the effects of various opioid agonists on high potassium-stimulated release of $[^3H]$ histamine. We have evaluated the properties of $non-{\mu},\;non-{\delta},$ binding of $[^3H]\;DIP\;([^3H]\;diprenorphine),$ anonselective opioid antagonist, in rat cortex membranes. Binding $to\;{\mu}\;and\;{\delta}$ sites was inhibited by the use of an excess of competing selective agonists (DAMGO, DPDPE) for these sites. (-) Ethylketocyclazocine (EKC), DIP and bremazocine inhibited $[^3H]$ DIP binding. However, arylacetamides (U69593 and U50488H) gave little inhibition Replacement of sodium by NMDG and the addition of guanine nucleotide influenced the inhibitory potency of (-) EKC, an agonist for {\kappa}_1-and-{\kappa}_2-binding site, but not of bremazocine. This result suggests that bremazocine can be an antagonist at this binding site. Also, we have examined the opioid modulation of $K^+(30mM)-induced\;[^3H]\;histamine$ release in rat frontal cortex slices labeled with $1-[^3H]\;histidine$. The $[^3H]\; histamine$ release from cortex slices was inhibited by EKC in a concentration-dependent manner. However, the ${\delta}$ receptor selective agonists, DPDPE and deltorphine II, ${\mu}$ receptor agonists, DAMGO and TAPS, ${\kappa}_1-agonists$, U69593 and U50488H, and ${\varepsilon}-agonist,\;{\beta}-endorphin,$ did not. The concentration-response curve of EKC was shifted to right in the presence of naloxone, nor-binaltorphimine and bremazocine, respectively. These results suggest that ${\kappa}_2$ opioid receptor regulates histamine release in the fromtal cortex of the rat.

• Journal of Ginseng Research
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• v.32 no.1
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• pp.1-7
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• 2008

Ginseng saponin has been shown to inhibit the development of dependence on morphine, cocaine, methamphetamine, but the antinarcotics effects of ginseng on nalbuphine remains still largely unknown. Ginseng administration attenuated the naloxone-induced jumping behavior on nalbuphine dependent mice. The development of morphine dependence was mediated through ${\mu}-opioid$ receptor, however, development of nalbuphine dependence was mediated through ${\kappa}-opioid$ receptor. However, it was found that the efficacy of analgesic antagonism of GTS was mediated through the serotonergic mechanism, not mediated through the opioid receptor. In addition, ginseng administration modulated cellular signal transduction in the brain. The increased NMDA receptor subunit (NR1, pNR1), phosphate extracellular signal regulated protein kinase (pERK), phosphate cAMP response element binding protein (pCREB) expression by nalbuphine was decreased by the administration of ginseng powder in cortex, hippocampus, striatum of rat brain. These results suggest that ginseng could be one of the targets of antinarcotic therapies to reduce the development of tolerance and dependence on nalbuphine as well as morphine.