• Title/Summary/Keyword: alpha-2 receptor

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Cloning of OLR1 Gene in Pig Adipose Tissue and Preliminary Study on Its Lipid-accumulating Effect

  • Sun, Chao;Liu, Chun-wei;Zhang, Zhong-pin
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.10
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    • pp.1420-1428
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    • 2009
  • In this study we cloned and characterized a novel lipid-accumulating gene, the oxidized low-density lipoprotein receptor 1 (OLR1), which is associated with lipogenesis. We analyzed the gene structure and detected the mRNA transcriptional expression levels in pig adipose tissues at different months of age (MA) and in different economic types (lean type and obese type) using real-time fluorescence quantitative PCR. OLR1 expression profile in different tissues of pig was analyzed. Finally, we studied the correlation between OLR1 and lipid metabolism related genes including peroxisome proliferator-activated $receptor{\gamma}2$ ($PPAR{\gamma}2$), fatty acid synthetase (FAS), triacylglycerol hydrolase (TGH), CAAT/enhancer binding protein $\alpha$ ($C/EBP{\alpha}$) and sterol regulatory element binding protein-1c (SREBP-1c). Results indicated that the OLR1 gene of the pig exhibited the highest homology with the cattle (84%), and the lowest with the mouse (27%). The signal peptide located from amino acid 38 to 60 and the domain from amino acid 144 to 256 were shared by the C-type lectin family. The expression level of OLR1 in pig lung was exceedingly higher than other tested tissues (p<0.01). In pig adipose tissue, the expression level of OLR1 mRNA increased significantly with growth (p<0.01). The expression level of OLR1 mRNA in obese-type pigs was significantly higher than that of lean-type pigs of the same monthly age (p<0.05). In adipose tissue, the expression of OLR1 correlated with $PPAR{\gamma}2$, FAS and SREBP-1c, but not TGH or C/EBP${\alpha}$. In conclusion, OLR1 was highly associated with fat deposition and its transcription, as suggested by high correlations, was possibly regulated by $PPAR{\gamma}2$ and SREBP-1c.

INFLUENCE OF TOTAL GINSENG SAPONIN ON VASOCONSTRICTORS -INDUCED CONTRACTILE RESPONSES IN THE RAT AORTA

  • Lim, Dong-Yoon;Hong, Jang-Gon;Chung, Choon-Hae;Ko, Suk-Tai
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.146-146
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    • 1998
  • The present study was designed to examine the effect of total ginseng saponin on contractile responses of vasoconstrictors in the rat aorta. Phenylephrine (an adrenergic ${\alpha}$$_1$-receptor agonist) and high potassium (a membrane depolarizing agent) caused greatly contractile responses in the rat aorta, respectively. However, in the presence of total ginseng saponin (600 $\mu\textrm{g}$/$m\ell$), the contractile responses of phenylephrine (10$\^$-5/ and 10$\^$-7/ M) and high potassium (3.5 ${\times}$ 10$\^$-2/ and 5.6 ${\times}$ 10$\^$-2/ M) were markedly potentiated whereas prostaglandin F$\sub$2${\alpha}$/ (5 ${\times}$ 10$\^$-6/ M)-induced contractile response was not affected. The contractile responses induced by phenylephrine (10$\^$-5/ M) and high potassium (3.5 ${\times}$ 10$\^$-2/ M) even in the presence of total ginseng saponin (600 $\mu\textrm{g}$/$m\ell$) were greatly inhibited by the pretreatment of nicardipine (10$\^$-6/ M), a calcium channel blocker. Taken together, these experimental results suggest that total ginseng saponin can enhance the contractile responses evoked by stimulation of adrenergic ${\alpha}$$_1$-receptor and the membrane depolarization in the rat aorta, which seems to be associated to calcium influx.

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Ligand-Independent Activation of the Androgen Receptor by Insulin-Like Growth Factor-I and the Role of the MAPK Pathway in Skeletal Muscle Cells

  • Kim, Hye Jin;Lee, Won Jun
    • Molecules and Cells
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    • v.28 no.6
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    • pp.589-593
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    • 2009
  • In this study, the roles of the p38 MAPK, ERK1/2 and JNK signaling pathway in IGF-I-induced AR induction and activation were examined. C2C12 cells were treated with IGF-I in the absence or presence of various inhibitors of p38 MAPK (SB203580), ERK1/2 (PD98059), and JNK (SP600125). Inhibition of the MAPK pathway with SB203580, PD98059, or SP600125 significantly decreased IGF-I-induced AR phosphorylation and total AR protein expression. IGF-I-induced nuclear fraction of total AR and phosphorylated AR were significantly inhibited by SB203580, PD98059, or SP600125. Furthermore, IGF-I-induced AR mRNA and skeletal ${\alpha}-actin$ mRNA were blocked by those inhibitors in dose-dependent manner. Confocal images showed that IGF-I-induced AR nuclear translocation from cytosol was significantly blocked by SB203580, PD98059, or SP600125, suggesting that the MAPK pathway regulates IGF-I-induced AR nuclear localization in skeletal muscle cells. The present results suggest that the MAPK pathways are required for the ligand-independent activation of AR by IGF-I in C2C12 skeletal muscle cells.

Insulin-Like Growth Factor-I-Induced Androgen Receptor Activation Is Mediated by the PI3K/Akt Pathway in C2C12 Skeletal Muscle Cells

  • Lee, Won Jun
    • Molecules and Cells
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    • v.28 no.5
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    • pp.495-499
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    • 2009
  • Although insulin-like growth factor-I (IGF-I) and androgen receptor (AR) are well known effectors of skeletal muscle, the molecular mechanism by which signaling pathways integrating AR and IGF-I in skeletal muscle cells has not been previously examined. In this study, the role of PI3K/Akt on IGF-I-induced gene expression and activation of AR in skeletal muscle cells was investigated. C2C12 cells were treated with IGF-I in the absence or presence of inhibitors of PI3K/Akt pathway (LY294002 and Wortmannin). Inhibition of the PI3K/Akt pathway with LY294002 or Wortmannin led to a significant decrease in IGF-I-induced AR phosphorylation and total AR protein expression. Furthermore, IGF-I-induced AR mRNA and skeletal ${\alpha}-actin$ mRNA were blocked by LY294002 or Wortmannin. Confocal images showed that IGF-I-induced AR translocation from cytosol to nucleus was inhibited significantly in response to treatment with LY294002 or Wortmannin. The present results suggest that modulating effect of IGF-I on AR gene expression and activation in C2C12 mouse skeletal muscle cells is mediated at least in part by the PI3K/Akt pathway.

Physiological characteristics of histamine receptor of the isolated renal artery in dog (개 적출 신동맥에 있어서 histamine receptor의 생리적 특성)

  • Kim, Joo-heon;Nam, Yun-jeong
    • Korean Journal of Veterinary Research
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    • v.29 no.2
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    • pp.19-24
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    • 1989
  • To elucidate the physiological characteristics of histamine receptor of the isolated renal artery in dog, effects of various receptor blockers and $Ca^{{+}{+}}$ channel blockers on the contractile responses of histamine were investigated in the isolated renal artery of dog. The results were summarized as follows: 1. Histamine caused the contraction in the isolated renal artery of dog, and the contractile responses increased between the concentration of $5{\times}10^{-6}M$ and $10^{-2}M$ in dose-dependent manner. 2. The contractile response induced by histamine ($10^{-3}M$) was not blocked by pretreatment with atropine ($10^{-6}M$), phentolamine ($10^{-6}M$), propranolol ($10^{-6}M$) or cimetidine ($10^{-6}M$), but was completely blocked by pretreatment with pyrilamine ($10^{-6}M$). 3. The contractility induced by histamine ($10^{-3}M$) was decreased in the $Ca^{{+}{+}}$ free medium. 4. The contractile response induced by histamine ($10^{-3}M$) was markedly inhibited by pretreatment with papaverine ($5{\times}10^{-5}M$) or verapamil ($5{\times}10^{-5}M$). 5. After the pre-contraction induced by norepinephrine ($10^{-7}M$) or prostaglandin $F2{\alpha}$ ($5{\times}10^{-6}M$), the contractile response induced by the additional treatment of histamine ($10^{-3}M$) was markedly increased compared with that of histamine ($10^{-3}M$) alone.

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Source of Ca++ and effect of adenosine triphosphate on the isolated renal artery of pig (돼지 적출 신동맥에 대한 adenosine triphosphate의 영향과 Ca++의 동원)

  • Nam, Yun-jeong;Kim, Joo-heon
    • Korean Journal of Veterinary Research
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    • v.31 no.3
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    • pp.253-258
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    • 1991
  • The aims of this study were to investigate the effect of adenosine triphosphate (ATP), which has been known as the neurotransmitter of nonadrenergic, noncholinergic nerves, and the source of $Ca^{\sharp}$ in the effect of ATP on the isolated renal artery of pig. The results of this study were summarized as follows: 1. ATP caused the contraction and the contractile responses were increased in a dose-dependent manner between the concentration of ATP $2{\times}10^{-3}M$ and $10^{-2}M$ on the isolated renal artery of pig. 2. The contractile responses induced by ATP $(5{\times}10^{-3}M)$ were not blocked by pretreatment with cholinergic receptor blocker (atropine, $10^{-6}M$), $\alpha$-adrenergic recptor blocker(phentolamine, $10^{-6}M$) or $\beta$-adrenergic receptor blocker (propranolol, $10^{-6}M$), and $H_1$-receptor blocker (pyrilamine, $10^{-6}M$) or $H_2$-receptor blocker (cimetidine, $10^{-6}M$) on the isolated renal artery of pig. 3. The contractile responses induced by ATP $(5{\times}10^{-3}M)$ were not appeared in $Ca^{\sharp}$-free medium. As the concentration of $Ca^{\sharp}$ in $Ca^{\sharp}$-free medium was increased, the contractile responses induced by ATP $(5{\times}10^{-3}M)$ were enhanced but were completely inhibited by pretreatment with $Ca^{\sharp}$-channel blocker, papaverine $(5{\times}10^{-5}M)$ or verapamil $(5{\times}10^{-5}M)$ on the isolated renal artery of pig.

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Studies on Digitalis Receptor Desensitization in Rat Ventricle (쥐 심실에서 Digitalis Receptor Desensitization에 관한 연구)

  • 이신웅;이정수;장태수
    • Biomolecules & Therapeutics
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    • v.2 no.2
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    • pp.114-119
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    • 1994
  • [$^3$H]Ouabain binding parameters ( $K_{D}$ and $B_{max}$) to control rat ventricular strips and Langendorff preparations which were not previously exposed to ouabain were compared with those to both preparations that had been first exposed to a complete ouabain dose range of dose-response curve (10$^{-8}$ to 10$^{4}$M). In rat ventricular strips and Langendorff perfused heart preparations, cumulative dose-response curves of ouabain revealed biphasic positive inotropic effects, a "low-dose" effect and a "high-dose" effect with E $d_{50}$ values of 0.5 $\mu$M and 35 $\mu$M ouabain, respectively. The "low-dose" effect in ventricular strip disappeared or was diminished significantly when the ouabain dose-response curve was repeated after the washout of the effects of the first dose-response curve, whereas there were no significant differences in the maximal "high-dose"effect in both exposures to oubain. However, both of the control and ouabain-preexposed Langendorff perfused hearts revealed the same low-dose effects. The $K_{D}$ value for [$^3$H] ouabain binding and the ouabain binding site concentration ( $B_{max}$) estimated by [$^3$H]ouabain displacement assay in control preparations were 230 nM and 2 pmol/mg protein, respectively. [$^3$H]Ouabain binding parameters were not changed by repeated exposure to high concentrations of ouabain. These results suggest that digitalis receptor desensitization in the rat ventricular strip may due to the change of post-receptor events induced by ouabain binding to a high affinity site ($\alpha$$_2$isoform).).).).).

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Antipsychotics for patients with pain

  • Shin, Sang Wook;Lee, Jin Seong;Abdi, Salahadin;Lee, Su Jung;Kim, Kyung Hoon
    • The Korean Journal of Pain
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    • v.32 no.1
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    • pp.3-11
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    • 2019
  • Going back to basics prior to mentioning the use of antipsychotics in patients with pain, the International Association for the Study of Pain (IASP) definition of pain can be summarized as an unpleasant experience, composed of sensory experience caused by actual tissue damage and/or emotional experience caused by potential tissue damage. Less used than antidepressants, antipsychotics have also been used for treating this unpleasant experience as adjuvant analgesics without sufficient evidence from research. Because recently developed atypical antipsychotics reduce the adverse reactions of extrapyramidal symptoms, such as acute dystonia, pseudo-parkinsonism, akathisia, and tardive dyskinesia caused by typical antipsychotics, they are expected to be used more frequently in various painful conditions, while increasing the risk of metabolic syndromes (weight gain, diabetes, and dyslipidemia). Various antipsychotics have different neurotransmitter receptor affinities for dopamine (D), 5-hydroxytryptamine (5-HT), adrenergic (${\alpha}$), histamine (H), and muscarinic (M) receptors. Atypical antipsychotics antagonize transient, weak $D_2$ receptor bindings with strong binding to the $5-HT_{2A}$ receptor, while typical antipsychotics block long-lasting, tight $D_2$ receptor binding. On the contrary, antidepressants in the field of pain management also block the reuptake of similar receptors, mainly on the 5-HT and, next, on the norepinephrine, but rarely on the D receptors. Antipsychotics have been used for treating positive symptoms, such as delusion, hallucination, disorganized thought and behavior, perception disturbance, and inappropriate emotion, rather than the negative, cognitive, and affective symptoms of psychosis. Therefore, an antipsychotic may be prescribed in pain patients with positive symptoms of psychosis during or after controlling all sensory components.

Studies on the Adrenotropic Receptors of Vas Deferens of Ditrema temmincki Bleeker (척출(剔出) 망상어 정관(精管)에 있어서 Adrenotropic Receptor 성질(性質)에 관(關)한 연구(硏究))

  • Sohn, Yong-Seuk;Hong, Ki-Whan
    • The Korean Journal of Pharmacology
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    • v.8 no.1
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    • pp.41-47
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    • 1972
  • The author studied the adrenotropic receptors of isolated vas deferens from Ditrema temmincki Bleeker, using adrenergic activators such as epinephrine, norepinephrine, isoproterenol and phenylephrine, and adrenergic blocking agents such as phenoxybenzamine and propranolol. The results are as follows: 1. The vas deferens was stimulated by epinephrine, norepinephrine and phenylephrine, but not affected by isoproterenol. 2. The excitatory effect of phenylephrine on the vas deferens was completely blocked by phenoxybenzamine, but more stimulated by propranolol. 3. The excitatory effects of epinephrine and norepinephrine were markedly reduced by phenoxybenzamine, but stimulated by propranolol. 4. The vas deferens pretreated with phenoxybenzamine and propranolol was not affected by epinephrine and norepinephrine. 5. The vas deferens was not affected by isoproterenol and also not affected by the pretreatment with either kind of blocking agent plus isoproterenol. 6. It seemed that the vas deferens had both alpha-excitatory receptor and beta-receptor, but it was difficult to detect the character of beta-receptor whether it was inhibitory or excitatory.

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The Studies on Glycogenolytic Adrenergic Receptor in Rat (흰쥐에서의 해당작용(解糖作用) Adrenergic Receptor에 대(對)한 검토(檢討))

  • Park, C.W.;Cha, I.J.
    • The Korean Journal of Pharmacology
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    • v.16 no.1 s.26
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    • pp.9-14
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    • 1980
  • To evaluate the adrenergic receptors for glycogenolytic responses to catecholamine, the blood glucose level, liver glycogen content and muscle glycogen level in rats were studied with treatment of epinephrine, norepinephrine and isoproterenol. In addition, to study the possibility of interconversion of adrenergic receptors, the effects of catecholamines in feeding animal were compared with those in fasting animal. The results are summarized as follow; 1) Epinephrine and norepinephine showed dose dependent increase of blood glucose level but the effect of isproterenol was not significant. 2) The prandial states of animal did not influence on effects of catecholamines on blood glucose level. 3) Liver glycogen contents were lowered by epinephrine or by norepinephrins but effect of isoproterenol was not significant. 4) Glycogen content of skeletal muscle was significantly lowered by isoproterenol and. epinephrine shifted the dose-response curve to right, but the effect of norepinephrine was not significant. 5) The effects of epinephrine and norepinephrine on blood glucose were significantly blocked by ergotamine but not by propranolol. These results indicate that the glycogenolytic response to adrenergic agents in rat is mediated by an alpha-receptor in liver and by a beta-receptor in skeletal muscle.

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