• 대한약리학회지
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• 제31권1호
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• pp.75-84
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• 1995

NO의 위산분비에 대한 작용을 규명하기 위하여 분리한 토끼위선세포에서 hypoxia/reoxygenation과 acidosis후 위산분비와 NO synthase 활성을 측정하였다. 분리한 위선세포에 30분의 hypoxia와 1시간의 reoxygenation을 주었으며, acidosis를 위하여 배지의 pH를 6.0과 4.0으로 변화시켜 실험하였다. 위산분비는 위선세포 내와 외의 $[^{14}C]-aminopyrine$ 축적비율로 측정하였으며, NO synthase 활성은 NO의 전구물질인 $[^{14}C]L-arginine$으로부터 $[^{14}C]-citrulline$으로의 전환율로 결정하였다. 결과로서 dibutyryl cAMP는 농도 의존적으로 위산분비를 촉진시켰으나 NO synthase 활성엔 영향을 주지 않았다. Hypoxia/reoxygenation은 기초 및 자극 위산분비를 억제하였으며 acidosis에 의해 위산분비억제는 더욱 심화되었다. Constitutive NO synthase 활성 역시 hypoxia/reoxygenation과 acidosis에 의해 억제되었다. 결론적으로 hypoxia/reoxygenation과 acidosis 같은 위점막의 병적상태는 위산분비와 NO 유리를 모두 억제하나, 기초상태의 위선에서 dibutyryl cAMP에 의한 위산분비 촉진에 대한 NO의 직접적인 작용은 확인되지 않았다.

• BMB Reports
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• 제39권4호
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• pp.400-405
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• 2006

A 16-month old boy was referred to our hospital for evaluation of recurrent generalized tonic clonic seizures. Metabolic evaluation revealed significant hyperammonemia ($1,112\;{\mu}g/dl$). Amino acid/acylcarnitine screening using tandem mass spectrometry showed markedly increased plasma levels of citrulline ($1,350\;{\mu}M/l$) with undetectable levels of arginine and arginosuccinic acid. Urinary excretion of citrulline was markedly increased ($38,617\;{\mu}M/g$ creatinine). Brain MRI findings showed diffuse high-signal intensity lesions, that involved gray and white matter in both frontal lobes and insula with edematous changes; these findings were consistent with the acute stage of citrullinemia (CTLN). Mutation analysis of the argininosuccinate synthetase (ASS) gene, in this patient, showed a Gly324Ser mutation in exon 13, and a 67-bp duplication mutation in exon 15 (c.1128-6_1188dup67). The patient was confirmed as having late-onset CTLN1 and treated with anticonvulsants, lactulose enema, protein restricted diet and arginine. Here we describe a case of late-onset CTLN1 in a patient by biochemical analyses and ASS gene mutation confirmation. This is the first report of a Korean patient with late-onset CTLN1 confirmed by ASS gene mutation identification.

• 유기물자원화
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• 제1권1호
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• pp.115-125
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• 1993

Euglena gracilis 에서 arginine deiminas는 mitochondrial matrix 내에 존재한다. 고도로 정제된 효소가 0.23 nM의 $K_m$ 값을 갖고 효소반응을 하기 위해서는 $Co^{2+}$가 필요하며, 이때 최적 pH는 9.3~10.3이었다. Gel filtration에 의해서 얻어진 조효소 단백질의 분자량은 87,000이었으며, SDS-acrylamide gel electrophoresis에 의해 효소는 48,000의 분자량을 갖는 2개의 동일한 subunit로 구성되어 있음이 밝혀졌다. Euglena의 arginine deiminas는 sulfhydryl inhibitors에 의해서 활성이 저지되었는데, 이는 sulfhydryl group이 효소의 활성부위에 관여함을 나타낸다. 이 sulfhydryl group은 arginine이 효소와 결합하는데 있어서 negative cooperativity를 나타내었다. ${\beta}-guanidinopropionate$, ${\gamma}-guanidinobutyrate$와 guanidinosuccinate는 효소의 활성을 저지시키지 않는데 반하여, $L-^{\alpha}-amino-{\beta}-guanidino-propionate$, D-arginine, 그리고 L-homoarginine은 효소의 활성을 강력하게 저지시켰다. Citrulline과 ornithine에 의해서도 상당한 정도의 효소활성저지가 관찰되었다. 우리는 Euglena의 arginine deiminase의 독특한 성질이 Euglena 라는 원생동물 내에서 arginine 대사의 조절에 어떻게 영향을 미치는지를 토의하고자 한다.

• Biomolecules & Therapeutics
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• 제7권2호
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• pp.105-111
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• 1999

Nitric oxide (NO), a cellular messenger synthesized from L-arginine by NO synthase (NOS, EC.1.14.13.39), is considered to be a regulator of gastric secretion. In the present study, the role of NO in the regulation of exocrine secretion was investigated in rat gastric chief cells. Treatment of chief cells with carba-chol resulted in an increase in the arginine conversion to citrulline, the amount of $NO_{x}$, the release of pepsine-gen, and the level of cGMP Especially, carbachol-stimulated increase of arginine to citrulline transformation, the amount of $NO_{x}$, cGMP level and the release of pepsinogen were partially reduced by the natural NOS inhibitor, $N^{G}$-monomethyl-L-arginine (MMA) and $N^{G}$, $N^{G}$-dimethyl-L-arginine (DMA). Furthermore, MMA- and DMA-induced decrease of pepsinogen secretion showed dose-dependent patters. Activation of NOS is one of the early events in receptor-mediated cascade of reactions in gastric chief cells and NO, not completely, but partially mediates gastric secretion. Agonist-stimulated pepsinogen secretion in chief cells has been considered to be mediated in adenosine 3',5'-cyclic monophosphate pathway and/or guanosine 3', 5'-cyclic monophosphate (cGMP) pathway. Taken together, the above results suggest that partial decrease of exocrine secretion following treatment of NOS inhibitor may result from the inactivation of NOS and subsequent guano- late cyclase, and NO/cGMP pathway may play a pivotal role in exocrine secretion.

• 한국미생물·생명공학회지
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• 제27권4호
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• pp.292-297
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• 1999

Overproduction of L-ornithine by mutant strains isolated from Brevibacterium detoglutamicum BK1046 was investigated. The strain was a L-ornithine auxotroph and exhibited culture instability during fermentation. Through a sequential screening effort, a highly stable strain with lless revertant formation was finally selected and designated B. ketoglutamicum BK52 (KCTC0141BP). It prouduced L-ornithine at a high concentration (above 9 g/L) independent of subculture or cultivation time, and also had a very low tendency of revertant formation. In a long-term storage, this strain maintained its cell stability and productivity of L-ornithine to a reasonable range.

• Journal of Yeungnam Medical Science
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• 제24권2호
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• pp.322-328
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• 2007

Ornithine transcarbamylase (OTC) deficiency is the most common inborn error of urea cycle metabolism; it is inherited in an X-linked manner. The OTC catalyzes the third step of the urea cycle, the conversion of ornithine and carbamyl phosphate to citrulline. Deficiency of OTC leads to the accumulation of ammonia, causing neurological deficits. In most affected hemizygote males, OTC deficiency manifests as hyperammonemic coma that often leads to death in the newborn period, and those who recover from the coma may be neurologically impaired due to the sequelae of the hyperammonemic encephalopathy. In some, late-onset manifestations develop. We report a male neonate with early onset OT deficiency that had apnea and was comatous. On mutation analysis using DNA sequencing after polymerase chain reaction (PCR) amplification of the 10 exons, deletions of 10 bases in codon 285, causing a frame shift was detected in exon 8. The mother and a sister were diagnosed as female carriers. Therefore, genetic counseling and the risk assessment could be provided to the family.

• Archives of Pharmacal Research
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• 제23권4호
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• pp.407-412
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• 2000

The presence of the nitric oxide synthase (NOS) enzyme from Salmonella typhimurium (S. typhimurium) was identified by measuring radiolabeled L-$[^3H]$citrulline and NO, and Western blot analysis. NOS was partially purified by both Mono Q ion exchange and Superose 12HR size exclusion column chromatography, sequentially. The molecular weight of NOS was estimated to be 93.3 kDa by Western blot analysis. The enzyme showed a significant dependency on the typical NOS cofactors; an apparent Km for L-arginine of 34.7 mM and maximum activity between $37^{\circ}C$ and $43^{\circ}C$. The activity was inhibited by NOS inhibitors such as aminoguanidine and $N^{G}$ $N^{G}$-dimethyl-L-arginine. taken together, partially purified NOS in S. typhimurium is assumed to be a different isoform of mammalian NOSs.OSs.

• Biomolecules & Therapeutics
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• 제2권2호
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• pp.131-135
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• 1994

The effect of ginsenoside (GS) from Panax ginseng on basal and nitro-L-arginine suppressed nitric oxide (NO) production was studied in rat kidney. NO production was determined by conversion to [$^{14C}$]=L-citrulline from [$^{14C}$]-L-arginine both in whole kidney and three renal segments; glomerulus, cortex excluding glomerulus (cortex-) and medulla. Nitro-L-arginine (total dose of 30 mg/kg/3 days, i.p.) significantly reduced NO production in whole kidney, which was prevented by GS pretreatment (30 mg/kg/3 days, i.p.). Relative high dose of GS (120 mg/kg/4 days, i.p..) selectively increased NO production in glomerulus and cortex-. Protein content, on wet weight basis, in cortex- and glomerular DNA content were significantly reduced by GS. Our results confirm the existence of constitutive nitric oxide synthase in kidney and it seems that target nephron segment for volume expansion due to GS'NO-mediated vasodilation and for NO production stimulated by GS is cortex including glomerulus.lus.

• Journal of Microbiology and Biotechnology
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• 제33권2호
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• pp.143-150
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• 2023

Sarcopenia is a condition in which muscle mass, strength, and performance decrease with age. It is associated with chronic diseases such as diabetes, cardiovascular disease, and hypertension, and contributes to an increase in mortality. Because managing sarcopenia is critical for maintaining good health and quality of life for the elderly, the condition has sparked concern among many researchers. To counteract sarcopenia, intake of protein is an important factor, while a lack of either protein or vitamin D is a major cause of sarcopenia. In addition, essential amino acids, leucine, β-hydroxy β-methylbutyrate (HMB), creatine, and citrulline are used as supplements for muscle health and are suggested as alternatives for controlling sarcopenia. There are many studies on such proteins and supplements, but it is necessary to actually organize the types, amounts, and methods by which proteins and supplements should be consumed to inhibit sarcopenia. In this study, the efficacy of proteins and supplements for controlling sarcopenia according to human clinical studies is summarized to provide suggestions about how the elderly may consume proteins, amino acids, and other supplements.

• 대한유전성대사질환학회지
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• 제15권1호
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• pp.29-34
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• 2015

시트룰린혈증은 유전적인 요인에 의하여 혈중에 암모니아를 비롯한 독성 물질이 축적되어 치명적인 임상 경과를 나타낼 수 있는 질환이다. 이 질환은 2가지 형태로 구분할 수 있으며, 유형별로 각기 다른 원인과 임상 양상을 보이는 것으로 알려져 있다. 시트룰린혈증 1형은 상염색체 열성유전 질환으로 암모니아를 간에서 요소로 합성하는 과정에 아르기니노숙신 생성효소(argininosuccinate synthethase)가 결핍되어 혈중 암모니아 농도와 혈중 시트룰린 농도의 증가와 혈중 아르기닌의 저하를 초래하게 되는 질환이다. 시트룰린혈증의 유병률은 50,000-60,000명당 1명 정도이다. 시트룰린 혈증은 임상 양상과 분자유전학적 특징에 따라 2가지 유형으로 구분할 수 있는데, 1형은 급성으로 신생아기에 발병하는 가장 흔한 형태이다. 환자는 출생시에는 특별한 증상을 보이지 않다가, 생후 3-4일을 지나면서 구토, 기면, 발작을 나타내게 되며 심하면 혼수 및 사망까지 이를 수 있다. 한편, 발병이 늦은 경우는 보다 드문 형태로 임상적으로 비교적 경한 증상을 나타낸다. 시트룰린혈증 1형은 9q34.1 염색체에 위치한 ASS1 유전자의 돌연변이에 의하여 아르기니노숙신 생성효소가 결핍되어 나타나며, 이 효소는 요소 회로에서 시트룰린과 아스파르트산이 아르기니노숙신으로 전환되는 과정을 담당한다. 따라서 ASS1 유전자의 돌연변이를 규명하는 것은 이 질병을 진단하는 데 분자유전학적으로 가장 확실한 방법이다. 저자들은 의심 증상을 가진 환자에게 조기에 시트룰린혈증 1형을 유전자 분석을 통하여 진단하였으며, 지속적 신대체 요법을 포함한 효과적인 급성기 치료 과정을 거쳐 현재 장기적인 식이 및 약물 치료를 성공적으로 진행 중에 있어, 이를 문헌 고찰과 함께 보고하는 바이다.