• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.243-251
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• 1998

Panax ginseng C.A. Meyer has been extensively used in the traditional oriental medicine as a restorative, tonic and prophylatic agent. Petroleum ether extract of panax ginseng C.A. Meyer (GPE) and its several fractions (PI-P5) were tested for the evaluation of antigenotoxicity against N-methyl-N-nitrosourea (MNU) and benzo(a)pyrene [B(a)P]-induced micronucleated reticulocytes in mouse peripheral blood. GPE and P2 showed more significant anticlastogenicity than other fractions did. To elucidate the anticlastogenic action mechanism of GPE and P2 against B(a)P, the alteration of B(a)P metabolism was studied. GPE and P2 inhibited B(a)P metabolism in the presence of 8-9 mix and decreased B(a)P-DNA binding in calf thymus DNA with 8-9 mix. They also decreased [$^3H$] MNU induced DNA binding and methylation to 7-methyl guanine and $O^{6}-methyl$ guanine adducts in calf thymus DNA by RPLC analysis. These results suggest that the anticlastogenicity of GPE and P2 on the B(a)P or MNU-induced clastogenicity is due to decrease of DNA binding with B(a)P or MNU, the inhibition of metabolism with B(a)P and the inhibition of methylation in DNA. Therefore, GPE and P2 may be useful chemopreventive agents of alkylating agent like MNU and secondary carcinogen like B(a)P.

• Applied Biological Chemistry
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• v.18 no.3
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• pp.167-176
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• 1975

As a study on the ATP-inhibited ribonuclease of Bacillus subtilis the screening work for obtaining the ATP-inhibited ribonuclease negative mutant were carried out. And mutant strain was selected by the treatment of N-methyl-N'-nitro-N-nitrosoguanidine (NTG). For the selected strain the enzyme purification and some physiological properties were examined and the results obtained were as follows. 1. Among tested 1817 strains with the treatment of NTG, 101 strain was selected as a mutant strain. 2. ATP-inhibited ribonuclease was tentatively purified by several independent column chromatography. The results with Sephadex G-75 column were 30 times purification, 99% recovery, and 20 times purification, 98% recovery, respectively. 3. ATP-inhibited ribonuclease was purified by 60 times through acid treatment, ammonium fractionation, and two successive chromatography. 4. The purified ribonuclease were shown to be effectively concentrated in robonnclease content and to have reduced numbers of protein band on Disc electrophoresis. 5. This enzyme degraded single-stranded RNA to 2',3'-cyclic AMP, 2',3'-cyclic CMP, 2',3,-cyclic GMP, 2',3'-cyclic UMP and some unknown intermediates. The enzyme could not split double-stranded RNA.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.33-33
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• 2001

본 연구는 한우 난포발달에 있어서 난포액 및 inhibin의 생리적 역할을 검토하기 위해 수행하였다. Anti-inhibin serum(AIS) 생산을 위해 사용된 항원은 porcine inhibin-$\alpha$-subunit 19~32의 peptide를 사용하여 adjuvant 용액을 1:3의 비율로 혼합하여 앙고라종 토끼 5두(체중 2.5kg)에게 주 2회 간격으로 8회 실시후 ELISA Leader로 항혈청의 역가를 확인하였다. 난포액(bFF; bovine follicular fluid)은 도축장에서 도축되는 한우 난소로부터 직경 1.0cm 이하의 난포로부터 회수하여 스테로이드를 제거하기 위해 10% chacoal solution(50 mg/$m\ell$, Norrit-A, Fisher Sci., USA)을 처리하여 45분간 배양후 원심분리후 상층액을 회수하여 실험에 공시하였다. 과립막세포의 체외배양을 위해 D-MEM용액(10% FCS와 antibiotics를 첨가)을 배양액으로 하여 1 $\times$ $10^{6}$ cells/$m\ell$로 조절하였다. 호르몬은 RIA 및 ELISA법으로 분석하였다. 그 결과 항원-항체반응은 항원처리후 24일째부터 항체가를 확인할 수 있었으며 52일째에서 높은 항원-항체반응을 보였다. 한편, 난포크기별 난포액의 progesterone 및 Estradiol-l7$\beta$을 농도를 분석한 결과, Progesterone 난포크기가 직경 1.0 cm부터 유의적으로 증가하기 시작하여 직경 2.0cm의 난포액에서는 높은 progesterone이 존재하고 있는 것으로 나타났다. 이에 반해, 난포크기별 난포액중 estradiol 17$\beta$농도는 직경 1.0cm구에서 가장 높게 나타났다. 난포직경이 1cm일 경우에 난포액내 etradiol-17$\beta$가 가장 많이 존재하고 있음이 나타났다. 과립막세포의 체외배양에서 배양 24시간에서는 과립막세포의 progesterone분비는 약 40ng/1$\times$$10^{6}$ cell/well/$m\ell$ 전후로 나타났으며 bFF 5%, AI 5% 및 bFF＋AI 첨가구에 따라 유의적인 차이는 없었다 반면에 48시간배양구에서는 24시간에 비해 유의적으로 높게 분비되었으며, bFF 5%처리구와 bFF5%＋AI5%처리구에서는 progesterone을 대조구보다 유의적으로 억제되었으나 AI 5%단독처리구에서는 대조구와 큰 차이가 없었다. 한편, 각 세포질을 SDS-PAGE로 분리하여 nitro cellulose membrane에 transfer하여 Western blotting법에 의해 검토한 결과, 직경 1.0 cm의 성숙난포의 granulosa cell에 특이하게 Inhibin이 존재하고 있음이 확인되었다. 이상의 결과로, 한우에 있어서 성숙난포에 존재하는 Inhibin은 난포발달 및 난포세포의 스테로이드호르몬합성에 중요하게 관여하고 있는 것으로 사료된다.

• The Korean Journal of Pain
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• v.23 no.1
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• pp.1-10
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• 2010

Background: Recent studies indicate that reactive oxygen species (ROS) are involved in persistent pain, including neuropathic and inflammatory pain. Since the data suggest that ROS are involved in central sensitization, the present study examines the levels of activated N-methyl-D-aspartate (NMDA) receptors in the dorsal horn after an exogenous supply of three antioxidants in rats with chronic post-ischemia pain (CPIP). This serves as an animal model of complex regional pain syndrome type-I induced by hindpaw ischemia/reperfusion injury. Methods: The application of tight-fitting O-rings for a period of three hours produced CPIP in male Sprague-Dawley rats. Allopurinol 4 mg/kg, allopurinol 40 mg/kg, superoxide dismutase (SOD) 4,000 U/kg, N-nitro-L-arginine methyl ester (L-NAME) 10 mg/kg and SOD 4,000 U/kg plus L-NAME 10 mg/kg were administered intraperitoneally just after O-ring application and on the first and second days after reperfusion. Mechanical allodynia was measured, and activation of the NMDA receptor subunit 1 (pNR1) of the lumbar spinal cord (L4-L6) was analyzed by the Western blot three days after reperfusion. Results: Allopurinol reduced mechanical allodynia and attenuated the enhancement of spinal pNR1 expression in CPIP rats. SOD and L-NAME also blocked spinal pNR1 in accordance with the reduced mechanical allodynia in rats with CPIP. Conclusions: The present data suggest the contribution of superoxide, produced via xanthine oxidase, and the participation of superoxide and nitric oxide as a precursor of peroxynitrite in NMDA mediated central sensitization. Finally, the findings support a therapeutic potential for the manipulation of superoxide and nitric oxide in ischemia/reperfusion related pain conditions.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.5
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• pp.369-378
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• 2000

This study was undertaken to investigate an involvement of nitroxergic innervation in gastric smooth muscle of rat. Isometric tension study, the measurement of single cell length, NADPH diaphorase stain of smooth muscle layers and neuronal nitric oxide synthase (nNOS) western blotting were performed. Sodium nitroprusside (SNP), a nitric oxide donor, relaxed the muscle strips precontracted by acetylcholine (ACh) in a concentration-dependent manner. Pretreatment of L-arginine decreased the contraction induced by electric field stimulation (EFS). Pretreatment of $N^G-nitro-L-arginine$ methyl ester (L-NAME), a NOS inhibitor, increased the EFS-induced contractions. LY 83583, a guanylate cyclase (GC) inhibitor, reversed the inhibitory actions of L-arginine on the muscle contractions. The effects of L-Arginine, L-NAME and LY 83583 on ACh-induced contractions were not significant. L-arginine reduced the EFS-induced contraction in circular muscle, whereas L-NAME enhanced the EFS-induced contraction in longitudinal strips. By EFS, the phasic contractions appeared approximately $20{\sim}25$ seconds later. L-NAME significantly shortened the delay time to about $2{\sim}3$ seconds. In single cell study, ACh contracted gastric smooth muscle cells, SNP relaxed the cells, and the latter also inhibited the ACh-induced contraction. LY 83583 enhanced the ACh-induced contraction and antagonized SNP-induced relaxation. NADPH diaphorase activity was assessed by a histochemistry, nitroblue tetrazolium (NTB) staining. Positive staining was observed in both circular and longitudinal muscle layers. L-arginine increased the staining, while L-NAME decreased the staining. Western blotting for nNOS proved the presence of nNOS in rat gastric smooth muscle. EFS and additional $Ca^{2+}$ increased nNOS protein expression. These results suggest that in rat stomach, both circular and longitudinal muscle layers are innervated with nitroxergic nerves which relax the gastric smooth muscle via NO-cGMP pathway.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.5
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• pp.297-303
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• 2012

This study was designed to elucidate high $K^+$-induced relaxation in the human gastric fundus. Circular smooth muscle from the human gastric fundus greater curvature showed stretch-dependent high $K^+$ (50 mM)-induced contractions. However, longitudinal smooth muscle produced stretch-dependent high $K^+$-induced relaxation. We investigated several relaxation mechanisms to understand the reason for the discrepancy. Protein kinase inhibitors such as KT 5823 (1 ${\mu}M$) and KT 5720 (1 ${\mu}M$) which block protein kinases (PKG and PKA) had no effect on high $K^+$-induced relaxation. $K^+$ channel blockers except 4-aminopyridine (4-AP), a voltage-dependent $K^+$ channel ($K_V$) blocker, did not affect high $K^+$ -induced relaxation. However, N(G)-nitro-L-arginine and 1H-(1,2,4)oxadiazolo (4,3-A)quinoxalin-1-one, an inhibitors of soluble guanylate cyclase (sGC) and 4-AP inhibited relaxation and reversed relaxation to contraction. High $K^+$-induced relaxation of the human gastric fundus was observed only in the longitudinal muscles from the greater curvature. These data suggest that the longitudinal muscle of the human gastric fundus greater curvature produced high $K^+$-induced relaxation that was activated by the nitric oxide/sGC pathway through a $K_V$ channel-dependent mechanism.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.4
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• pp.185-191
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• 2008

Activation of c-Jun N-terminal kinase (JNK), a member of the mitogen-activated protein kinase family, is an important cellular response that modulates the outcome of the cells which are exposed to the tumor necrosis factor (TNF) or the genotoxic stress including DNA damaging agents. Although it is known that JNK is activated in response to genotoxic stress, neither the pathways to transduce signals to activate JNK nor the primary sensors of the cells that trigger the stress response have been identified. Here, we report that the receptor interacting protein (RIP), a key adaptor protein of TNF signaling, was required to activate JNK in the cells treated with certain DNA damaging agents such as adriamycin (Adr) and 1-${\beta}$-D-arabinofuranosylcytosine (Ara-C) that cause slow and sustained activation, but it was not required when treated with N-methyl-N-nitro-N-nitrosoguanidine (MNNG) and short wavelength UV, which causes quick and transient activation. Our findings revealed that this sustained JNK activation was not mediated by the TNF (tumor necrosis factor) receptor signaling, but it required a functional ATM (ataxia telangiectasia) activity. In addition, JNK inhibitor SP-600125 significantly blocked the Adr-induced cell death, but it did not affect the cell death induced by MNNG. These findings suggest that the sustained activation of JNK mediated by RIP plays an important role in the DNA damage-induced cell death, and that the duration of JNK activation relays a different stress response to determine the cell fate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.139-147
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• 1981

In this study, by using Landrock method modified by Yokozeki (1973) and Koizumi (1980), water activity ($a_w$) of various model preparations of Kamaboko was measured and ability of lowering $a_w$ of humectants added such as sodium chloride, sugars and polyols was discussed. The results were as follows : 1 The effect of sodium chloride on lowering aw was the highest among all of examined. When $4\%$ sodium chloride as humectant was added to the model Kamaboko, the $a_w$ was reduced to 0.94 or below. 2. Among the sugars, glucose was so effective that it lowered $a_w$ to 0.96 by adding $10\%$, but it would cause browning reaction on the Kamaboko surface. 3. Glycerin was the most effective among the polyols. When it was added by $10\%$, the $a_w$ of Kamaboko was reduced to 0.95. 4. It was more effective to decrease $a_w$ to lower moisture content of model Kamaboko.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.6
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• pp.405-413
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• 2011

This study was designed to elucidate high-$K^+$ induced response of circular and longitudinal smooth muscle from human gastric corpus using isometric contraction. Contraction from circular and longitudinal muscle stripes of gastric corpus greater curvature and lesser curvature were compared. Circular smooth muscle from corpus greater curvature showed high $K^+$ (50 mM)-induced tonic contraction. On the contrary, however, longitudinal smooth muscle strips showed high $K^+$ (50 mM)-induced sustained relaxation. To find out the reason for the discrepancy we tested several relaxation mechanisms. Protein kinase blockers like KT5720, PKA inhibitor, and KT5823, PKG inhibitor, did not affect high $K^+$-induced relaxation. $K^+$ channel blockers like tetraethylammonium (TEA), apamin (APA), glibenclamide (Glib) and barium ($Ba^{2+}$) also had no effect. However, N(G)-nitro-L-arginine (L-NNA) and 1H-(1,2,4) oxadiazolo (4,3-A) quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase (sGC) and 4-AP (4-aminopyridine), voltage-dependent $K^+$ channel (KV) blocker, inhibited high $K^+$ -induced relaxation, hence reversing to tonic contraction. High $K^+$-induced relaxation was observed in gastric corpus of human stomach, but only in the longitudinal muscles from greater curvature not lesser curvature. L-NNA, ODQ and KV channel blocker sensitive high $K^+$-induced relaxation in longitudinal muscle of higher portion of corpus was also observed. These results suggest that longitudinal smooth muscle from greater curvature of gastric corpus produced high $K^+$-induced relaxation which was activated by NO/sGC pathway and by $K_V$ channel dependent mechanism.

• YAKHAK HOEJI
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• v.41 no.3
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• pp.389-398
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• 1997

Non-adenergic non-cholinergic (NANC) innervation on the circular muscle of the rabbit gastric body was investigated by observing the magnitudy of relaxations induced by the elec trical field stimulation (EFS). Strips were cut from the greater curvature of the gastric body and stimulated with 5s trains of 0.5 ms pulses at 1-20 Hz, 40 V. The EFS induced transient frequency-dependent contractons, followed by a slowly recovering relaxation ewpecially at higher frequency of the EFS. In the presence of atropine and guanethidine, the contractions were virtually abolished, while the frequency-dependent relaxations by the EFS remained unaffected. The magnitude of relaxations progressively decreased as the location of the strips gets closer to the bottom of the gastric body. The relaxations were ablished by tetrodotoxin, indicating that their orgin is the NANC nerve stimulation. NG-nitro-L-arginine (L-NNA, 10-$100{\mu}M$), the inhibitor of nitric oxide (NO)-synthase, caused a concentration-dependent inhibition of the NANC relaxations. The inhibitory effects of L-NNA were not affected gy the location of the strips and were reversed by L-arginine, the precursor of NO-biosynthesis. Hemoglobin (20-$60{\mu}M$), a NO scavenger, inhibited the NANC relaxation s in a concentration-dependent manner. This inhibition was more prominent in the NANC relaxations observed in the lower portion of the gastric body and the relaxations induced ly lower frequencies of the EFS. Methyelne blue (10-$100{\mu}M$), an inhibitor of cytosolic guanylate cyclase, markedly inhibited the NANC relaxations, almost abolishing the response at a higher dose ($100{\mu}M$). These results suggest that NANX innervation of the rabbit gastric body progeressively decrease as he location of the strips gets closer to the bottom of the gastric body, and that the NANC relaxation is primarily mediated by NO-guanosine 3',5'-cyclic monophophate (cyclic GMP).