• The Korean Journal of Physiology and Pharmacology
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• 제21권2호
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• pp.241-249
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• 2017

Plasma membrane hyperpolarization associated with activation of $Ca^{2+}$-activated $K^+$ channels plays an important role in sperm capacitation during fertilization. Although Slo3 (slowpoke homologue 3), together with the auxiliary ${\gamma}^2$-subunit, LRRC52 (leucine-rich-repeat-containing 52), is known to mediate the pH-sensitive, sperm-specific $K^+$ current KSper in mice, the molecular identity of this channel in human sperm remains controversial. In this study, we tested the classical $BK_{Ca}$ activators, NS1619 and LDD175, on human Slo3, heterologously expressed in HEK293 cells together with its functional interacting ${\gamma}^2$ subunit, hLRRC52. As previously reported, Slo3 $K^+$ current was unaffected by iberiotoxin or 4-aminopyridine, but was inhibited by ~50% by 20 mM TEA. Extracellular alkalinization potentiated hSlo3 $K^+$ current, and internal alkalinization and $Ca^{2+}$ elevation induced a leftward shift its activation voltage. NS1619, which acts intracellularly to modulate hSlo1 gating, attenuated hSlo3 $K^+$ currents, whereas LDD175 increased this current and induced membrane potential hyperpolarization. LDD175-induced potentiation was not associated with a change in the half-activation voltage at different intracellular pHs (pH 7.3 and pH 8.0) in the absence of intracellular $Ca^{2+}$. In contrast, elevation of intracellular $Ca^{2+}$ dramatically enhanced the LDD175-induced leftward shift in the half-activation potential of hSlo3. Therefore, the mechanism of action does not involve pH-dependent modulation of hSlo3 gating; instead, LDD175 may modulate $Ca^{2+}$-dependent activation of hSlo3. Thus, LDD175 potentially activates native KSper and may induce membrane hyperpolarization-associated hyperactivation in human sperm.

• The Korean Journal of Physiology and Pharmacology
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• 제23권5호
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• pp.381-392
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• 2019

Sperm function and male fertility are closely related to pH dependent $K^+$ current (KSper) in human sperm, which is most likely composed of Slo3 and its auxiliary subunit leucine-rich repeat-containing protein 52 (LRRC52). Onion peel extract (OPE) and its major active ingredient quercetin are widely used as fertility enhancers; however, the effect of OPE and quercetin on Slo3 has not been elucidated. The purpose of this study is to investigate the effect of quercetin on human Slo3 channels. Human Slo3 and LRRC52 were co-transfected into HEK293 cells and pharmacological properties were studied with the whole cell patch clamp technique. We successfully expressed and measured pH sensitive and calcium insensitive Slo3 currents in HEK293 cells. We found that OPE and its key ingredient quercetin inhibit Slo3 currents. Inhibition by quercetin is dose dependent and this degree of inhibition decreases with elevating internal alkalization and internal free calcium concentrations. Functional moieties in the quercetin polyphenolic ring govern the degree of inhibition of Slo3 by quercetin, and the composition of such functional moieties are sensitive to the pH of the medium. These results suggest that quercetin inhibits Slo3 in a pH and calcium dependent manner. Therefore, we surmise that quercetin induced depolarization in spermatozoa may enhance the voltage gated proton channel (Hv1), and activate non-selective cation channels of sperm (CatSper) dependent calcium influx to trigger sperm capacitation and acrosome reaction.

• 한국응용과학기술학회지
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• 제9권1호
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• pp.15-23
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• 1992

This study was aimed to observe dose-response effects of squid liver oil enriched in n3 polyunsaturated fatty acids(n-3 PUFA) on the metabolism of streptozotocint(STZ)-induced diabetic rats. In this experiment, 24 STZ-induced diabetic male rats of Sprague Dawley strain were divided into 4 groups and fed for 4 weeks with basal diet(0%). 33%,67% and 100% squid liver oil(SLO) of total fat content, and 6 normal rats were fed with 0% SLO diet at the same time. The results obtained were as follows: 1. Rat group fed with 33% SLO diet showed the least body weight loss and changes in blood glucose, while ones of 100% SLO diet showed the highest level. 2. Serum total protein and ratio of albumin to globulin of all the groups were below the standard level, but did not show significantly different among diet groups. 3. Serum creatinine concentration of all the groups were stayed whthin normal range, but BUN were 3 to 4 times higher than normal rats. BUN concentration of rats fed with 0% and 33% SLO diet was significantly lower than those of others. 4. Total-cholesterol level of serum increased in all the groups except 33% SLO diet, but since HDL-chol, levels and TG concentration went up with an incerase of SLO in the diets, the ratio of HDL-chol. to total-chol, of rats fed with 67% and 100% SLO diet showed higher than those with 0%, and 33% SLO, and TG concentration of rats fed with 67% and 100% SLO diet decreased significantly.

• Asian-Australasian Journal of Animal Sciences
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• 제25권6호
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• pp.869-879
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• 2012

This study was conducted to investigate the effects of dietary lipid source and level on growth performance, blood parameters, fatty acid composition and flesh quality of sub-adult olive flounder Paralichthys olivaceus. Eight experimental diets were formulated to contain 5% squid liver oil (SLO), 5% linseed oil (LO), 5% soybean oil (SO), a mixture of 1% squid liver oil, 2% linseed oil and 2% soybean oil (MIX), no lipid supplementation with high protein level (LL-HP), 10% squid liver oil (HL-SLO), a mixture of 1% squid liver oil, 4.5% linseed oil and 4.5% soybean oil (HL-VO), and 1% squid liver oil with high starch level (LL-HC), respectively. Two replicate groups of fish (average initial weight of 296 g) were fed the diets for 17 wks. After 5 wks, 11 wks and the end of the feeding trial, five fish from each tank were randomly sampled for analysis of body composition. At the end of the feeding trial, final mean weight of fish fed the LL-HP diet was significantly (p<0.05) higher than that of fish fed the HL-VO diet, but did not differ significantly from those of fish fed the SLO, LO, SO, MIX, HL-SLO and LL-HC diets. Fish fed the LL-HP diet showed significantly higher feed efficiency than fish fed the LO, HL-SLO and HL-VO diets. Feed efficiency of fish fed the LO, SO and MIX diets were similar to those of fish fed the SLO and HL-SLO diets. Fish fed the HL-SLO diet showed significantly higher total cholesterol content in plasma compared with other diets. Fatty acid composition of tissues was reflected by dietary fatty acid composition. The highest linoleic (LA) and linolenic acid (LNA) contents in the dorsal muscle were observed in fish fed the SO and LO diets, respectively, regardless of feeding period. The highest eicosapentaenoic acid (EPA) content in the dorsal muscle was observed in fish fed the LL-HP and LL-HC diets after 11 and 17 weeks of feeding, respectively. Fish fed the SLO and HL-SLO diets showed higher docosahexaenoic acid (DHA) content than that of other treatments after 11 and 17 weeks of feeding, respectively. Dietary inclusion of vegetable oils reduced n-3 HUFA contents in the dorsal muscle and liver of fish. The n-3 HUFA contents in tissues of fish fed the SLO and HL-SLO diets were higher than those of fish fed other diets, except for the LL-HP and LL-HC diets. Hardness, gel strength, chewiness and cohesiveness values of dorsal muscle in fish were significantly affected by dietary lipid source. The results of this study indicate that fish oil in fish meal based diets for sub-adult olive flounder could be replaced by soybean oil and linseed oil without negative effects on growth and feed utilization.

• Preventive Nutrition and Food Science
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• 제3권3호
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• pp.216-220
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• 1998

Lipoxygenase inhibitory acitivity of the methanolic extract of 60 different kinds of plant seeds was determined by a spectrophotometric method using a soybean lipoxigenase(SLO) and linolenic acid. Among the extracts examined, the methanolic extract of nutmeg(Myristical fragrans)seed showed the most potent SLO inhibitory activity. To isolate SLO inhibitor, hence, the defatted methanol extract was further partitioned with ether, ehtylacetate , and n-butanol , stepwise. The ether souble fraction was successively chromatographed on silica gel, Sephadex LH-20 and preparative TLC. Three phenolic compounds were isolated , and one of them showing a strong SLO inhibition activity was identified as a 2,6-dihydroxy-9-(3', 4', -dihydroxyphenyl)nonylphenone (IC50a=0.39$\mu\textrm{g}$/ml) by 1H-& 13C0NMR, IR, and MS spectroscopy.

• Preventive Nutrition and Food Science
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• 제3권4호
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• pp.315-319
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• 1998

Previously, the methanolic extract of Paeonia moutan seeds was found to potently inhibit soybean lipoxy-genase (SLO). Hence to isolate SLO inhibitor, the defattd methaniolic extract of the seeds was consecutively partitioned wiht ether, ethyl acetate,n-butanol ,adn water. The ether souble fraction showing strong inhibitory activity against SLO was further fractionated into a strongly acidic, a weakly acidic, and a neutral fractions. The strongly acidic components of the ether extract were successively subjected to chromatography on a silica gel, Sephadex LH-20, and preparative HPLC. Four phenolic compounds were isolated , and twio of them showing a strong SLO inhibition activity were identified as luteolin (IC50=2.32$\mu\textrm{g}$/ml) and 5,6,4'-trihydroxy-7,3'- dimethoxylflavone (IC50=0.31$\mu\textrm{g}$/ml) by UV, IR, 1H-& 13C-NMR, and MS spectroscopy. In addition, two flavonoids showed significantly antioxidative activity as strong as that of of $\alpha$-tocopherol (p<0.05) in the autoxidation system of linoleic acid. These results suggest that luteolin and 5,6,4'-trihydroxy-7,3'-dimethoxy-flavone may be used as a potential source of anti-inflammatory agents with antioxidative activity.

• Applied Biological Chemistry
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• 제14권3호
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• pp.229-235
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• 1971

우리나라에서 재배되고 있는 대표적인 수도 품종 중에서 japonica type으로 관옥, 후지사까 5호, 팔달, 수원 82호의 4품종과 indica type으로 IR-262 CP-slo의 2품종을 선정하여 estel형 인 유기인계 살충제 malathion과 방향족 ester로서 p-nitrophenyl acetate에 대한 esterase의 활성을 비교해 보고 agar-gel electrophoresis에 의하여 ${\alpha}-naphthyl$ acetate를 기질로 하여 esterase의 zymogram을 관찰한 바를 요약해 보면 다음과 같다. 1. 조효소액(crude enzyme)의 malathion가수분해 능력을 효소액일정량에 대한 분해된 malathion milligram으로 비교하면 관옥>IR-262>후지사까 5호>CP-slo>팔달>수원 82호의 순으로 관옥이 가장 활성이 강하고 팔달, 수원 82호가 가장 약하다. 2. Esterase zymogram을 보면 품종간에 대차없이 $3{\sim}4$개의 band가 두극으로 움직이며 cathode로 특히 굵고 진한 band가 있고 수원 82호는 다른 품종과 약간 다른 pattern을 보였다. 3. p-Nitrophenyl acetate를 기질로 할 때 매 milligram 단백질당의 흡광도로 활성을 비교하면 CP-slo>IR-262>팔달>관옥>수원 82호>후지사까 5호의 순으로 indica type의 품종이 훨씬 활성이 강하나 malathion 경우와 일치하지는 않는다. 4. 0.2ppm 정도의 malathion으로 벼의 esterase는 별로 저해 되지 않았다. 5. 발아중인 벼종자에는 malathion과 p-nitrophenyl acetate를 가수분해하는 복합 esterase가 존재 할 것으로 추측된다.

• Fisheries and Aquatic Sciences
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• 제13권2호
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• pp.127-132
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• 2010

A study was conducted to investigate the effects of dietary lipid sources on the growth and fatty acid composition of juvenile sea cucumber. For 12 weeks, three replicate groups of sea cucumber (average weight 1.4 g) were fed one of three diets, containing squid liver oil (SLO), soybean oil (SO), or linseed oil (LO) as a dietary lipid source, or a control diet (CON) without added lipids. Sea cucumber survival was not significantly different among dietary treatments (P>0.05). The highest weight gain was observed in sea cucumber fed the SLO diet, whereas the weight gain of sea cucumber fed the SO diet was the lowest among dietary treatments (P<0.05). No significant differences were found in the moisture, crude protein, crude lipid, and ash contents of whole sea cucumber body among dietary treatments (P>0.05). Concentrations of 20:5n-3 and 22:6n-3 were significantly higher in sea cucumber fed the SLO diet than in those fed on the other diets. The highest 18:2n-6 and 18:3n-3 contents were observed in sea cucumber fed the SO and LO diets, respectively. The results of this study suggest that squid liver oil could be used as a good lipid source in formulated diets for juvenile sea cucumber.

• 전력전자학회논문지
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• 제8권1호
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• pp.17-23
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• 2003

컴퓨터 모니터를 통해 안구망막의 형태와 두께를 보기 위해서 레이저의 경로차를 이용하는 SLO 장비가 사용되고 있다. 이러한 방법으로 망막의 선명한 3차원 영상을 보기 위해서는 레이저 광경로 시스템의 정확한 동기제어가 필요하다. 이 영상을 얻기 위해서는 평면주사를 하는데 있어서 정밀동기제어가 매우 중요하다. 본 논문에서는 안구의 3차원 영상을 만들기 위해 갈바노미터의 동기제어를 구현한다. 또한 갈바노미터의 간략한 수학적 모델의 타당성을 보인다.

• 한국수산과학회지
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• 제49권3호
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• pp.317-322
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• 2016

This study was carried out to investigate the effects of various dietary lipid sources on the growth performance, body composition, and fatty acid profiles of juvenile fancy carp (Cyprinus carpio var. koi). Three replicate groups of fish (initial mean body weight, 15.1±0.18 g) were fed one of five experimental diets containing fish oil (SLO), soybean oil (SO), linseed oil (LO), lard (LA), or a mixture of SLO, SO, and LO (Mix) for 8 weeks. Fish fed the LA diet gained less weight than did fish fed the LO diet. The feed efficiency and protein efficiency ratio of fish fed the LA and Mix diets were lower than those of fish fed the SO and LO diets. The body lipid content of fish fed the SO diet was lower than those of the other groups. Whole-body fatty acid compositions reflected the fatty acid compositions of dietary lipid sources. Fish fed the SO diet had high concentrations of linoleic acid and arachidonic acid, whereas fish fed the LO diet were rich in linolenic acid. Fish fed the SLO diet had significantly higher levels of eicosapentaenoic acid and docosahexaenoic acid compared with fish fed the SO, LO, and LA diets. The results of this study suggest that SO or LO could be used as a replacement for SLO in the diets of juvenile fancy carp without any negative effects on growth and feed utilization when the dietary essential fatty acid requirements are satisfied for juvenile fancy carp.