• International Journal of Oral Biology
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• 제43권4호
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• pp.209-216
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• 2018

Reactive oxygen species (ROS) and nitrogen species (RNS) are involved in cellular signaling processes as a cause of oxidative stress. According to recent studies, ROS and RNS are important signaling molecules involved in pain transmission through spinal mechanisms. In this study, a patch clamp recording was used in spinal slices of rats to investigate the action mechanisms of $O_2{^{{\bullet}_-}}$ and NO on the excitability of substantia gelatinosa (SG) neuron. The application of xanthine and xanthine oxidase (X/XO) compound, a ROS donor, induced inward currents and increased the frequency of spontaneous excitatory postsynaptic currents (sEPSC) in slice preparation. The application of S-nitroso-N-acetyl-DL-penicillamine (SNAP), a RNS donor, also induced inward currents and increased the frequency of sEPSC. In a single cell preparation, X/XO and SNAP had no effect on the inward currents, revealing the involvement of presynaptic action. X/XO and SNAP induced a membrane depolarization in current clamp conditions which was significantly decreased by the addition of thapsigargin to an external calcium free solution for blocking synaptic transmission. Furthermore, X/XO and SNAP increased the frequency of action potentials evoked by depolarizing current pulses, suggesting the involvement of postsynaptic action. According to these results, it was estblished that elevated ROS and RNS in the spinal cord can sensitize the dorsal horn neurons via pre- and postsynaptic mechanisms. Therefore, ROS and RNS play similar roles in the regulation of the membrane excitability of SG neurons.

• 한국양식학회지
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• 제19권2호
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• pp.140-146
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• 2006

This study was conducted to investigate the effect of dietary oxidized oil and ${\alpha}$-tocopherol level on growth and body composition of juvenile flounder. To prepare oxidized diets, squid liver oil was oxidized by aeration at $25^{\circ}C$ for 30 days. The six diets were prepared to contain 6% fresh or oxidized squid liver oil as the lipid sources in combination with three levels of ${\alpha}$-tocopheryl acetate at 0, 80 and 800 mg/kg diet. Triplicate groups of fish ($3.9{\pm}0.1$) were fed to apparent satiation twice a day for 8 weeks. Survival was not significantly different among treatments. Weight gain, feed efficiency, daily feed intake, protein efficiency ratio and condition factor of fish fed the fresh oil diets were significantly higher than those of fish fed the oxidized oil diets (P<0.05). The increase of the vitamin E level in diets did not result in any significant improvement on growth performance of fish fed both oil diets. The vitamin E content of the liver and dorsal muscle increased with increasing dietary vitamin E level at both oil diet groups. A decreasing trend in vitamin E content of the tissues was observed in fish fed the oxidized oil diets at the same dietary vitamin E level. Significantly higher moisture content and lower crude lipid content were observed in the whole body of fish fed the oxidized oil diets than fish fed the fresh oil diets (P<0.05). Dietary lipid source affected the fatty acid content of the whole body; higher contents of saturated and monoenoic fatty acids, and lower n-3 HUFA contents such as 20:5n-3 and 22:6n-3 were observed in fish fed the oxidized oil diets than those of fish fed fresh oil diets. The results of this study suggest that the dietary oxidized oil may impair the growth performance, and an increase in ${\alpha}$-tocopheryl acetate supplementation have no beneficial effect on growth and feed efficiency of juvenile flounder.

• 한국양식학회지
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• 제8권3호
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• pp.195-207
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• 1995

겨울철 동해안에서 어획되어 식용으로 널리 이용되는 중요 어종중의 하나인 장갱이, Stichaeusgyigorjewi Herzenstein를 1994년 2월 25일과 1995년 2월 16일부터 2월 24일까지 총 5회에 걸쳐 경북 울진군 원남면 오산항에서 구입하여, 실내수조에서 자연산란을 유도하였고 그 난발생을 연구하였다. 구입된 어미의 평균전장, 체장 및 중량은 각각 암컷에서 55.62cm, 50.66cm, 1,192.74g이었고, 수컷에서는 52.85cm, 48.26cm, 및 612.58g으로 수컷에 비해 암컷의 체장에 대한 중량의 비가 높았다. 산란은 수조에 수용한 후 평균 4일 만에 이루어졌고, 산란시의 수온은 $9.2\~ll.0^{\circ}C$였다. 암컷 총 57마리중 40마리가 실내에서 산란하여 $70.2\%$의 자연산란률을 보였고, 암컷 1 마리당 평균산란수는 227,200개였다. 산란은 주로 새벽에 이루어졌고 1회에 거의 전량 백색의 반투명한 타원형 난괴의 형태로 산란하였으며, 그 난괴의 크기는 평균장경 20.32cm, 평균단경 14.57cm 및 평균중량 803.7g이었다. 수정이 완료된 후에도 수컷은 계속 알을 보호하였다. 수정난의 평균난경은 1.54mm, 평균난황경은 1.12mm였으며, 평균직경 0.37mm의 유구 1개를 갖는다. 산란된 알의 평균수정률, 발안률 및 부화율은 각각 $85.7\%,\;80.4\%$ 및 $63.2\%$였다 평균수온 $13.2^{\circ}C$에서 수정란의 수정후 발생 단계별 소요시간은 2세포기까지 5시간 25분, 상실기 13시간, 포배기 18시간, 후기 낭배기 57시간 20분이었으며, 66시간 35분에 배체가 형성되었다. 그 후 발생이 진행되어 368시간 50분만에 약 $10\%$의 자어가 부화되었고, 425시간 30분에는 전체 부화자어의 약 $90\%$가 부화되었다.