• Title/Summary/Keyword: receptor I

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Circulating levels of vitamin D, vitamin D receptor polymorphisms, and colorectal adenoma: a meta-analysis

  • Lee, Jung-Eun
    • Nutrition Research and Practice
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    • v.5 no.5
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    • pp.464-470
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    • 2011
  • Growing evidence suggests an elevated risk for colorectal neoplasia among individuals with low levels of vitamin D, the biological actions of which are mediated by the vitamin D receptor (VDR). To investigate the association among vitamin D status, VDR polymorphisms (FokI, and BsmI), and colorectal adenoma, we conducted a meta-analysis of nine studies of circulating levels of 25-hydroxyvitamin D (25(OH)D) and five studies of FokI or BsmI polymorphisms in relation to colorectal adenomas. Study-specific relative risks (RRs) and 95% confidence intervals (CIs) were pooled using a random-effects model. A total of 3398 coloreetal adenomas for 25(OH)D and 1754 colorectal adenomas for VDR were included in the meta-analysis. We identified a significant inverse association between colorectal adenoma (combined RR, 0.93; 95% CI, 0.87-0.98 per 10 ng/mL increase in 25(OH)D levels). When we examined FokI and BsmI polymorphisms in the meta-analysis, we found no association for either FokI (combined RR, 1.00; 95% CI, 0.95-1.06) or BsmI (combined RR, 0.99; 95% CI, 0.93-1.05) in the additive model. These data suggest an inverse association between circulating 25(OH)D levels and colorectal adenoma risk.

DED Interaction of FADD and Caspase-8 in the Induction of Apoptotic Cell Death

  • Park, Young-Hoon;Han, Chang Woo;Jeong, Mi Suk;Jang, Se Bok
    • Journal of Microbiology and Biotechnology
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    • v.32 no.8
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    • pp.1034-1040
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    • 2022
  • Fas-associated death domain (FADD) is an adapter molecule that bridges the interaction between receptor-interacting protein 1 (RIP1) and aspartate-specific cysteine protease-8 (caspase-8). As the primary mediator of apoptotic cell death, caspase-8 has two N-terminal death-effector domains (DEDs) and it interacts with other proteins in the DED subfamily through several conserved residues. In the tumor necrosis receptor-1 (TNFR-1)-dependent signaling pathway, apoptosis is triggered by the caspase-8/FADD complex by stimulating receptor internalization. However, the molecular mechanism of complex formation by the DED proteins remains poorly understood. Here, we found that direct DED-DED interaction between FADD and caspase-8 and the structure-based mutations (Y8D/I128A, E12A/I128A, E12R/I128A, K39A/I128A, K39D/I128A, F122A/I128A, and L123A/I128A) of caspase-8 disrupted formation of the stable DED complex with FADD. Moreover, the monomeric crystal structure of the caspase-8 DEDs (F122A/I128A) was solved at 1.7 Å. This study will provide new insight into the interaction mechanism and structural characteristics between FADD and caspase-8 DED subfamily proteins.

Effects of Amiloride on $A_{1}$ Adenosine Receptor-Adenylyl Cyclase System in Rat Adipocytes (흰쥐 지방세포에 있어서 Amiloride의 $A_{1}$ Adenosine Receptor- Adenylyl Cyclase System에 대한 작용)

  • Park, Kyung-Sun;Lee, Myung-Soon;Kim, Kyung-Hwan
    • The Korean Journal of Pharmacology
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    • v.29 no.2
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    • pp.245-252
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    • 1993
  • Amiloride is a potassium sparing duretic which specifically inhibits $Na{^+}$ channels. In the present study, we investigated the possible interaction of amiloride with $A_1$ adenosine receptors-adenylyl cyclase system in crude adipocytic plasma membrane fractions prepared from Sprague-Dawley rats. When the function of $G_i$ protein (inhibitory guanine nucleotide binding protein) was assessed by determining the effects of GTP on isoproterenol-stimulated adenylyl cyclase activity, the inhibitory effect of high concentrations of GTP was not observed in the presence of amiloride. In contrast, the adenosine receptor-mediated inhibition of the enzyme activity, as determined empolying 2-chloroadenosine, was either unchanged or even more enhanced by amiloride depending on the concentrations of 2-chloroadenosine. Thus, it appears that GTP- and receptor-mediated inhibitory function of $G_{i}$ proteins can be separated from one another. Receptor-mediated function of $G_{s}$ protein did not appear to be significantly affected by amiloride, since the inhibition of isoproterenol-stimulated adenylyl cyclase activity by propranolol under the same conditions was not significantly altered by amiloride. The enhancement of 2-chloroadenosine-mediated inhibition of adenylyl cyclase by amiloride was maintained in the presence of 150 mM NaCl. In summary, these results suggest that amiloride interacts both with $A_{l}$ adenosine receptors and with $G_i$ proteins in adipocytic membranes. Its binding to the $A_1$ adenosine receptors appears to facilitate the coupling of the receptors with $G_i$ proteins thereby enhancing the inhibition of isoproterenol-stimulated adenylyl cyclase activity by $A_1$ adenosine agonist, and the direct interaction with $G_i$ proteins appears to remove the GTP-dependent inhibitory effect on adenylyl cyclase activity.

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Inhibitory Effects of Glycine on Morphine-Induced Hyperactivity, Reverse Tolerance and Postsynaptic Dopamine Receptor Supersensitivity in Mice

  • Shin, Kyung-Wook;Hong, Jin-Tae;Yoo, Hwan-Soo;Song, Sukgil;Oh, Ki-Wan
    • Archives of Pharmacal Research
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    • v.26 no.12
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    • pp.1074-1078
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    • 2003
  • The effects of glycine on morphine-induced hyperactivity, reverse tolerance and postsynaptic dopamine receptor supersensitivity in mice was examined. A single administration of morphine (10 mg/kg, s.c.) induced hyperactivity as measured in mice. The morphine-induced hyperactivity was inhibited by pretreatment with glycine (100, 200 and 400 mg/kg, i.p.). In addition, it was found repeated administration of morphine (10 mg/kg, s.c.) to mice daily for 6 days caused an increase in motor activity which could be induced by a subsequent morphine dose, an effect known as reverse tolerance or sensitization. Glycine (100, 200 and 400 rng/kg, i.p.) also inhibited morphine-induced reverse tolerance. Mice that had received 7 daily repeated administrations of morphine also developed postsynaptic dopamine receptor supersensitivity, as shown by enhanced ambulatory activity after administration of apomorphine (2 mg/kg, s.c.). Glycine inhibited the development of postsynaptic dopamine receptor supersensitivity induced by repeated administration of morphine. It is suggested that the inhibitory effects of glycine might be mediated by dopaminergic (DAergic) transmission. Accordingly, the inhibition by glycine of the morphine-induced hyperactivity, reverse tolerance and dopamine receptor supersensitivity suggests that glycine might be useful for the treatment of morphine addiction.

A Study on Antiestrogenic Effects of Tamoxifen in Immature Rat Uterus; I. Effects on Concentrations of Cytosol and Nuclear Estradiol Receptor (미성숙 쥐 자궁에서 Tamoxifen의 Antiestrogen 효과에 관한 연구 : I. 세포질 내 및 핵 내 Estradiol 수용체 농도의 변화에 관하여)

  • Lee, Hyo-jong;Jo, Choong-ho;Park, Moo-hyun
    • Korean Journal of Veterinary Research
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    • v.25 no.2
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    • pp.187-195
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    • 1985
  • The Present study has been carried out to elucidate the antiestrogenic effects of tamoxifen in uteri of immature rats. Immature female Sprague-Dawley rats were allocated into 4, groups and injected with $5{\mu}g$ of estradiol-$17{\beta}$, $50{\mu}g$ of tamoxifen, a combination of both or vehicle only subcutaneously three times after an interval of 24 hours respectively. The concentrations, of cytosol estradiol receptor in uterus were measured by DCC method before and 1, 3, 6, 12, 24, 48 and 72 hours after the above treatments and those of nuclear estradiol were measured by protamine exchange method 72 hours and those of nuclear estradiol were measured by protamine exchange method 72 hours after the above treatments. The results obtained were summarized as follows: 1. The binding affinity of tamoxifen to estradiol receptor in uterine cytosol was lower than that of estradiol-$17{\beta}$, accordingly the translocation of estradiol receptor into the nucleus was found to be delayed. 2. Tamoxifen caused the retention of estradiol receptor in nucleus over 24 hours and inhibited the replenishment of the receptor from nucleus to cytosol in uterus.

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AluI RFLP Analysis of the Calcitonin Receptor Gene in the Korean Athletic Men (한국인 남성 운동 선수군에서 Calcitonin Receptor 유전자의 AluI RFLP 분석)

  • 장대호;황영철;강병용;최성숙;강진양;하남주
    • YAKHAK HOEJI
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    • v.48 no.1
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    • pp.75-81
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    • 2004
  • Bone mineral density (BMD) is influenced by genetic and environmental factors. Among genetic study; calcitonin receptor (CTR) gene is a good candidate influencing the inter-individual difference in BMD because CTR is involved in calcium and bone metabolism. Thus, we investigated the distribution of C1377T polymorphism in the CTR gene among male Korean elite athletic and control groups, respectively and also an association with BMD in lumbar spine and femoral neck. Our results suggested that this polymorphism of CTR gene was not significantly associated with lumbar spine or femoral neck BMDs in the both groups, respectively. However, we found that there was the racial difference in genotype distribution of this polymorphism between Caucasian and Asian populations. Though we could not detect the significant association between C1377T polymorphism of CTR gene and lumbar spine or femoral neck BMDs, further studies using other ethnic groups are necessary to clarify the precise role in BMD of CTR gene.

Effect of imipramine or ECS on central $\beta_1$and $\beta_2$receptor Sensitivity in the Cardiovascular Response of Rat

  • Sohn, Uy-Dong;Kim, Choong-Young;Huh, In-Hoi
    • Archives of Pharmacal Research
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    • v.12 no.4
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    • pp.282-288
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    • 1989
  • This study was investigated the effects of imipramine (IMI) and electroconvulsive shock (ECS), which are used as antidepressant therapy, on the central $\beta_1$or $\beta_2$ adrenergic receptor in anesthetized rats. The resting blood pressure and heart rate decreased in reserpinized group (5 mg/kg i. p., 24 hr before), but not in order 4 groups i. e. acute IMI (20 mg/kg i. p.. 3-5 hr before), chronic IMI (Same dose, twice a day for 14 days), siggle ECS (sinusoidal 20 Hz, 120 V for 2 sec) and repeated ECS (same condition, daily for 12 days). The increase of heart rate and hypotension evoked by 1 or 3 $\mu$g intracerebroventricular (i. c. v.) administration of (+) dobutamine, $\beta_2$-agonist, 1 or 3 $\mu$g i. c. v. was significantly attenuated in repeated ECS or reserpine treatment. And, the diminuation of pulse pressure of salbutamol also reduced by repeated ECS. These results suggest that IMI or ECS result in attenuation on tachycardia by (+) dobutamine or on hypotension by salbutamol, presumably by which the central $\beta_1$ or $\beta_2$receptor sensitivity may be suppressed, repectively.

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5-HT1A receptors mediate the analgesic effect of rosavin in a mouse model of oxaliplatin-induced peripheral neuropathic pain

  • Li, Daxian;Park, Sangwon;Lee, Kyungjoon;Jang, Dae Sik;Kim, Sun Kwang
    • The Korean Journal of Physiology and Pharmacology
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    • v.25 no.5
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    • pp.489-494
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    • 2021
  • Oxaliplatin, a third-generation platinum derivative, is the mainstay of current antineoplastic medications for advanced colorectal cancer therapy. However, peripheral neuropathic complications, especially cold allodynia, undermine the life-prolonging outcome of this anti-cancer agent. Rosavin, a phenylpropanoid derived originally from Rhodiola rosea, exhibits a wide range of therapeutic properties. The present study explored whether and how rosavin alleviates oxaliplatin-induced cold hypersensitivity in mice. In the acetone drop test, cold allodynia behavior was observed from days 3 to 5 after a single injection of oxaliplatin (6 mg/kg, i.p.). Cold allodynia was significantly attenuated following rosavin treatment (10 mg/kg, i.p.). Specific endogenous 5-HT depletion by three consecutive pretreatments with parachlorophenylalanine (150 mg/kg/day, i.p.) abolished the analgesic action of rosavin; this effect was not observed following pretreatment with naloxone (opioid receptor antagonist, 10 mg/kg, i.p.). Furthermore, 5-HT1A receptor antagonist WAY-100635 (0.16 mg/kg, i.p.), but not 5-HT3 receptor antagonist MDL-72222 (1 mg/kg, i.p.), blocked rosavin-induced analgesia. These results suggest that rosavin may provide a novel approach to alleviate oxaliplatin-induced cold allodynia by recruiting the activity of 5-HT1A receptors.

A sporadic case of Loeys-Dietz syndrome type I with two novel mutations of the TGFBR2 gene

  • Ha, Jung-Sook;Kim, Yeo-Hyang
    • Clinical and Experimental Pediatrics
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    • v.54 no.6
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    • pp.272-275
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    • 2011
  • A recently recognized connective tissue disorder, Loeys-Dietz syndrome (LDS) is a genetic aortic aneurysm syndrome caused by mutations in the transforming growth factor-receptor type I or II gene (TGFBR1 or TGFBR2). They have distinctive phenotypic abnormalities including widely spaced eyes (hypertelorism), bifid uvula or cleft palate, and arterial tortuosity with aortic aneurysm or dissection throughout the arterial tree. LDS is characterized by aggressive and rapid progression of aortic aneurysm. Therefore, the patients with distinct phenotype, marked aortic dilatation and aneurysm at early age should be suspected to be affected by LDS and rapid TGFBR gene analysis should be done. We report one child diagnosed as LDS due to typical phenotypes and two novel missense mutations of the TGFBR2 gene (c.1526G>T and c.1528A>T).

Spinal and Peripheral GABA-A and B Receptor Agonists for the Alleviation of Mechanical Hypersensitivity following Compressive Nerve Injury in the Rat (백서에서 신경압박 손상에 의해 유발된 과민반응에서 척추 및 말초 GABA-A와 B 수용체 작용제에 의한 완화효과)

  • Jeon, Young Hoon;Yoon, Duck Mi;Nam, Taick Sang;Leem, Joong Woo;Paik, Gwang Se
    • The Korean Journal of Pain
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    • v.19 no.1
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    • pp.22-32
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    • 2006
  • Background: This study was conducted to investigate the roles of the spinal and peripheral ${\gamma}$-aminobutyric acid (GABA)- ergic systems for the mechanical hypersensitivity produced by chronic compression of the dorsal root ganglion (CCD). Methods: CCD was performed at the left 5th lumbar dorsal root ganglion. The paw withdrawal threshold (PWT) to von Frey stimuli was measured. The mechanical responsiveness of the lumbar dorsal horn neurons was examined. GABAergic drugs were delivered with intrathecal (i.t.) or intraplantar (i.pl.) injection or by topical application onto the spinal cord. Results: CCD produced mechanical hypersensitivity, which was evidenced by the decrease of the PWT, and it lasting for 10 weeks. For the rats showing mechanical hypersensitivity, the mechanical responsiveness of the lumbar dorsal horn neurons was enhanced. A similar increase was observed with the normal lumbar dorsal horn neurons when the GABA-A receptor antagonist bicuculline was topically applied. An i.t. injection of GABA-A or GABA-B receptor agonist, muscimol or baclofen, alleviated the CCD-induced hypersensitivity. Topical application of same drugs attenuated the CCD-induced enhanced mechanical responsiveness of the lumbar dorsal horn neurons. CCD-induced hypersensitivity was also improved by low-dose muscimol applied (i.pl.) into the affected hind paw, whereas no effects could be observed with high-dose muscimol or baclofen. Conclusions: The results suggest that the neuropathic pain associated with compression of the dorsal root ganglion is caused by hyperexcitability of the dorsal horn neurons due to a loss of spinal GABAergic inhibition. Peripheral application of low-dose GABA-A receptor agonist can be useful to treat this pain.