• 한국수정란이식학회지
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• 제16권2호
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• pp.79-89
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• 2001

배분화과정시 나타나는 $Ca^{2+}$ 변화에 미치는 $E_2$의 영향을 알아보고자 whole cell voltage clamp 기법, 방사선 등위원소 면역측정법, 그리고 공초점 현미경을 통하여 $E_2$처리 후 나타나는 $Ca^{2+}$ 전류 변화 및 세포내 $Ca^{2+}$ 농도 변화를 조사하였다. 생쥐의 미성숙 난자는 난소의 난포를 천자하고, 배란난자는 과배란 처리 후 난관에서 회수하였다. 수정란은 과배란 처리 후 수컷 생쥐와 교미를 유도한 후 각각의 단계에 맞는 수정란을 채란하였다. 혈중 $E_2$의 농도는 심장을 천자하여 혈액을 채취한 후 배발달 단계와 호르몬 처리 시간이 일치하는 혈액만을 사용하였다. 본 실험의 결과를 요약하면 다음과 같다. 1. $E_2$처리시 미성숙난자의 제 1극체 형성률 (성숙의 지표)은 $E_2$를 처리하지 않은 난자(83% : 83/100)보다 $E_2$를 처리한 난자 (94%, 94/100)에서 유의적 (P<0.05)으로 높게 나타났다. 2. $E_2$를 처리하였을 때 $Ca^{2+}$ 내향전류의 변화는 -10 mV에서 -1.23$\pm$0.01 nA (n=15)에서 -1.50$\pm$0.03 nA (n=15)로 122% 상승함으로써 유의한 (P<0.05) 변화를 보였다. 3. $E_2$를 처리하지 않은 난자 및 수정란을 1로 한 후 $E_2$를 처리한 난자 및 수정란의 변화를 상대적인 값으로 표시하였다. $E_2$처리한 난자는 1.22$\pm$0.17 (n=10), $E_2$처리한 전핵배는 1.20$\pm$0.14 (n=10), $E_2$처리한 2세포기배는 1.07$\pm$0.01 (n=10), 4세포기배는 1.05$\pm$0.09 (n=10)를 나타냄으로써 수정란의 단계마다 $E_2$의 반응 결과가 차이가 남을 알 수 있었다. 4. $E_2$농도 곡선에서 PMSG 처리 후 $E_2$의 혈중농도는 계속적인 상승을 보이다가 배란시기에 최고치를 나타내었으며, 배란 후 다시 감소하여 8세포기에서는 급격한 감소현상이 나타났다. 이후 다시 상실기를 거쳐 배반포기 임신기간동안 $E_2$의 농도가 상승하였다. 5. $E_2$처리 후 세포내 $Ca^{2+}$ 농도변화의 결과로, $E_2$를 처리하지 않은 난자들의 세포내 $Ca^{2+}$ 농도는 836.4$\pm$131.2 (n=10), $E_2$를 처리한 난자들은 1736.4$\pm$192.0 (n=10)로써 유의한 (P<0.05) 차이를 보였다. 이상의 결과로부터 $E_2$처리에 의한 세포내 $Ca^{2+}$ 농도 상승은 $E_2$가 $Ca^{2+}$ 통로를 자극함으로써 세포바깥의 $Ca^{2+}$이 세포안으로 이동하여 나타나는 변화로 생각된다.

• The Korean Journal of Physiology and Pharmacology
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• 제4권6호
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• pp.427-437
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• 2000

The early studies of cardiac and smooth muscle cells provided evidence for two different calcium channels, the L-type (also called high-voltage activated [HVA]) and T-type (low-voltage activated [LVA]). These calcium channels provided calcium for muscle contractions and pace-making activities. As might be expected, the number of different calcium channels increased when researchers studied neurons and the identification of the neuronal calcium channels has proven to be much more difficult than with the muscle calcium channels. There are two reasons for this difficulty; (1) a larger number of different calcium channels in neurons and (2) many of the different calcium channels have similar kinetic properties. This review uses the N-type calcium channel to illustrate the difficulties in identifying and characterizing calcium channels in neurons. It shows that the discovery of toxins that can specifically block single calcium channel types has made it possible to easily and rapidly discern the physiological roles of the different calcium channels in the neuron, Without these toxins it is unlikely that progress would have been as rapid.

• Molecules and Cells
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• 제21권1호
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• pp.52-62
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• 2006

In previous reports we demonstrated that ginsenosides, active ingredients of Panax ginseng, affect some subsets of voltage-dependent $Ca^{2+}$ channels in neuronal cells expressed in Xenopus laevis oocytes. However, the major component(s) of ginseng that affect cloned $Ca^{2+}$ channel subtypes such as ${\alpha}_{1C}$(L)-, ${\alpha}_{1B}$(N)-, ${\alpha}_{1A}$(P/Q)-, ${\alpha}_{1E}$(R)- and ${\alpha}_{1G}$(T) have not been identified. Here, we used the two-microelectrode voltage clamp technique to characterize the effects of ginsenosides and ginsenoside metabolites on $Ba^{2+}$ currents ($I_{Ba}$) in Xenopus oocytes expressing five different $Ca^{2+}$ channel subtypes. Exposure to ginseng total saponins (GTS) induced voltage-dependent, dose-dependent and reversible inhibition of the five channel subtypes, with particularly strong inhibition of the ${\alpha}_{1G}$-type. Of the various ginsenosides, $Rb_1$, Rc, Re, Rf, $Rg_1$, $Rg_3$, and $Rh_2$, ginsenoside $Rg_3$ also inhibited all five channel subtypes and ginsenoside $Rh_2$ had most effect on the ${\alpha}_{1C}$- and ${\alpha}_{1E}$-type $Ca^{2+}$ channels. Compound K (CK), a protopanaxadiol ginsenoside metabolite, strongly inhibited only the ${\alpha}_{1G}$-type of $Ca^{2+}$ channel, whereas M4, a protopanaxatriol ginsenoside metabolite, had almost no effect on any of the channels. $Rg_3$, $Rh_2$, and CK shifted the steady-state activation curves but not the inactivation curves in the depolarizing direction in the ${\alpha}_{1B}$- and ${\alpha}_{1A}$-types. These results reveal that $Rg_3$, $Rh_2$ and CK are the major inhibitors of $Ca^{2+}$ channels in Panax ginseng, and that they show some $Ca^{2+}$ channel selectivity.

• 대한치과마취과학회지
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• 제14권1호
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• pp.41-47
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• 2014

Background: Autophagy is a self-eating process that is important for balancing sources of energy at critical times in development and in response stress. Autophagy also plays a protective role in removing clearing damaged intracellular organelles and aggregated proteins as well as eliminating intracellular pathogens. The purpose of the present study was to examine the protective effect of propofol against hypoxic damage using keratinocytes. Methods: Human keratinocytes (HaCaT cells) were obtained from the American Type Culture Collection. Propofol which were made by dissolving them in DMSO were kept frozen at $-4^{\circ}C$ until use. The stock was diluted to their concentration with DMEM when needed. Prior to propofol treatment cells were grown to about 80% confluence and then exposed to propofol at different concentrations (0, 25, 50, 75, $100{\mu}M$) for 2 h pretreatment. Cell viability was measured using a quantitative colorimetric assay with thiazolyl blue tetrazolium bromide (MTT assay), and fluorescence microscopy and western blot analysis were used for evaluation of autophagy processes. Results: The viability of propofol-treated HaCaT cells was increased in a dose-dependent manner. Propofol did not show any significant toxic effect on the HaCaT cells. The autophagy inhibitor, 3-methyladenine, reduced cell viability of hypoxia-injured HaCat cells. Fluorescence microscopy and western blot analysis showed propofol induce autophagy pathway signals. Conclusions: Propofol enhanced viability of hypoxia-injured HaCaT cells and we suggest propofol has cellular protective effects by autophagy signal pathway activation.

• 공업화학
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• 제9권3호
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• pp.317-321
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• 1998

수열 방법으로 합성한 기체 분리용 제올라이트 흡착제의 분자체 및 이온교환 특성을 파악하기 위하여 KCl, $CaCl_2$, $YCl_3$ 그리고 $InCl_3$으로 제올라이트에 함유된 Na 이온을 치환시켰다. 치환시킨 X형 제올라이트를 $25^{\circ}C$에서 $CO_2$가스로 그리고 합성 제올라이트에 대하여 $O_2$, $N_2$가스로 부피법 장치를 통해 평형 흡착 특성을 각각 비교하였다. 측정결과를 Freundlich, Langmuir 그리고 Toth형 model 식을 이용하여 변수를 파악하였으며, 제올라이트의 $CO_2-PSA$ 흡착공정에 적용가능성을 측정하기 위하여 흡착파괴실험을 실시하고, 이를 PSA 공정 simulation에 적용하였다. 여기서 X형 제올라이트는 공정 배가스에서 $CO_2$회수에 적합한 흡착제로 사용할 수 있음을 확인하였다.

• 암석학회지
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• 제11권3_4호
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• pp.121-137
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• 2002

옥천변성대의 변성진화사를 밝히기 위한 연구는 지난 수십여년간 많은 학자들에 의해 수행되어 왔다. 그 결과 옥천변성대의 변성조건이 약 $490-630^{\circ}C$, 4.2-9.4 kbar에 해당되는 중온-중압형에 속함이 밝혀졌고, 또한 시계방향의 압력-온도-시간 경로를 경험했음이 알려졌다. 이러한 결과는 드러스트 나페에 의해 옥천변성대의 지각 두께가 증가했음을 지시한다. 그러나 변성작용에 관련된 조산운동을 규명하는데는 여러 가지 어려움이 남아 있다 특히 변성시기에 대한 논란은 오랫동안 거듭되어 왔으며, 최근의 연구 결과는 옥천변성대의 최고변성작용 시기를 석탄기와 페름기의 경계 부근인 약 300-280 Ma로 규정짓는다 따라서 옥천변성대와 태백산분지는 별개의 지구조구로서 서로 다른 진화 과정을 겪었으리라 추정되며, 이들은 약 250-220 Ma사이에 봉합되어 옥천대를 형성했을 가능성이 있다. 이와 같은 결과는 옥천대의 진화과정에 대한 기존의 생각과 일부 배치되며 새로운 지체구조적 파라다임을 요구한다. 또한 옥천대가 일본의 히다연변대-히다변성대에 대비될 수 있음을 시사한다.

• The Korean Journal of Physiology and Pharmacology
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• 제21권6호
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• pp.687-694
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• 2017

Plumbagin, a hydroxy 1,4-naphthoquinone compound from plant metabolites, exhibits anticancer, antibacterial, and antifungal activities via modulating various signaling molecules. However, its effects on vascular functions are rarely studied except in pulmonary and coronary arteries where NADPH oxidase (NOX) inhibition was suggested as a mechanism. Here we investigate the effects of plumbagin on the contractility of skeletal artery (deep femoral artery, DFA), mesenteric artery (MA) and renal artery (RA) in rats. Although plumbagin alone had no effect on the isometric tone of DFA, $1{\mu}M$ phenylephrine (PhE)-induced partial contraction was largely augmented by plumbagin (${\Delta}T_{Plum}$, 125% of 80 mM KCl-induced contraction at $1{\mu}M$). With relatively higher concentrations (>$5{\mu}M$), plumbagin induced a transient contraction followed by tonic relaxation of DFA. Similar biphasic augmentation of the PhE-induced contraction was observed in MA and RA. VAS2870 and GKT137831, specific NOX4 inhibitors, neither mimicked nor inhibited ${\Delta}T_{Plum}$ in DFA. Also, pretreatment with tiron or catalase did not affect ${\Delta}T_{Plum}$ of DFA. Under the inhibition of PhE-contraction with L-type $Ca^{2+}$ channel blocker (nifedipine, $1{\mu}M$), plumbagin still induced tonic contraction, suggesting $Ca^{2+}$-sensitization mechanism of smooth muscle. Although ${\Delta}T_{Plum}$ was consistently observed under pretreatment with Rho A-kinase inhibitor (Y27632, $1{\mu}M$), a PKC inhibitor (GF 109203X, $10{\mu}M$) largely suppressed ${\Delta}T_{Plum}$. Taken together, it is suggested that plumbagin facilitates the PKC activation in the presence of vasoactive agonists in skeletal arteries. The biphasic contractile effects on the systemic arteries should be considered in the pharmacological studies of plumbagin and 1,4-naphthoquinones.

• 생약학회지
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• 제46권2호
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• pp.160-166
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• 2015

Yijung-tang (YJT) is a traditional herbal formula comprising 4 medicinal herbs. In the present study, we performed the simultaneous analysis for three compounds of YJT and examined anti-allergic effects in vitro. The column for separation of three compounds was used Gemini C18 column and maintained at 40$^{\circ}C$. The mobile phase for gradient elution consisted of two solvent systems. To evaluate Th2 chemokines, YJT was treated into tumor necrosis factor (TNF)-${\alpha}$ and interferon (IFN)-${\gamma}$-stimulated HaCaT cells, and performed ELISA for thymus and activation regulated chemokine (TARC) and regulated on activation, normal T-cell expressed and secreted (RANTES). To measure Th2 cytokines, YJT was added into primary mouse splenocytes, and performed ELISA for interleukin (IL)-4, 5, 13. Calibration curves were acquired with r² >0.9999. The contents of liquiritin, glycyrrhizin, and 6-gingerol in YJT were 4.50 mg/g, 11.10 mg/g, and 1.33 mg/g, respectively. YJT inhibited production of TARC and RANTES in TNF-${\alpha}$ and IFN-${\gamma}$-treated HaCaT cells. YJT also reduced production of IL-4, 5, and 13 in primary mouse splenocytes. In conclusion, our data will be a valuable information to improve quality control and anti-allergic effects of YJT.

• International Journal of Oral Biology
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• 제43권1호
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• pp.5-11
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• 2018

Recent findings indicate that Type 2 taste receptors (T2Rs) are expressed outside the gustatory system, including in the gastrointestinal tracts and the exocrine glands, such as the submandibular (SM), parotid (P), lacrimal (L) glands and pancreas (PC). Specifically, T2Rs are found in some of the gastrointestinal endocrine cells, and these cells secreted peptide hormones in response to stimulation by bitter-tasting compounds. The results show that T2Rs may have significant physiological roles besides bitter taste reception. The functions of the T2Rs in the exocrine glands remain poorly understood. An expression levels analysis of T2Rs will help to determine those functions in the exocrine glands. The expression levels of the T2Rs in the exocrine glands were discovered via the qPCR. C57BL/6J mice of 42~60-day-old were used. Messenger RNAs were extracted from S, P, L and PC. Cloned DNAs were synthesized by reverse transcription. Quantitative PCRs were performed using the SYBR Green method. The expression levels of the T2Rs were calculated as relative expression levels to that of the GAPDH. The statistical significance among the observed exocrine glands was tested using the variance analysis (ANOVA test). Tas2r108, out of murine 35 T2Rs, was the most highly expressed in every observed exocrine gland. This finding was similar to previous results from tongue papillae, but the expression levels were lower than those of the tongue papillae. Tas2r137 of SM, P, L and PC were expressed a little lower than that of tongue papillae. The T2Rs in the exocrine glands may play slightly different roles from those in the tongue. We suggest that physiological studies such as a patch clamp and functional $Ca^{2+}$ imaging of acinar cells are necessary for understanding the Tas2r108 functions.

• 한국작물학회지
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• 제44권1호
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• pp.59-63
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• 1999

Yield and growth characteristics were compared for five rice cultivars; a new Tongil-type, so called "super-rice", Dasanbyeo, an old Tongil-type Milyang 23, two japonicas Dongjinbyeo and Ilpumbyeo, and a new plant type (NPT)line IR65600-27-1-2. The objective of this stusy was to clarify the high yielding capacity of Dasanbyeo in terms of growth characteristics. The average grain yield (9 t/ha) of Dasanbyeo was higher than that of Milyang 23 by ca. 9% that of japonicas by 20 to 30%, and that of NPT line by ca. 100%. The higher grain yield of Dasanbyeo was attributable not only to the greater dry matter production but also to the higher harvest index (HI). Dasanbyeo showed the greatest dry matter at harvest owing not only to the rapid leaf expan-sion at early growth stage and the resulting high LAI through the entire growth stage but also to the high NAR despite the high LAI. The rapid leaf expansion of Dasanbyeo at early growth stage seemed to be related in part to the profuse tillering capacity. HI was 0.53 in Dasanbyeo, 0,51 in Milyang 23, 0.41 in japonicas, and 0.35 in NPT line. Dasanbyeo was indebted for its higher HI to the relatively high grain filling ratio in spite of a much greater sink size than the other cultivars. Dasan had a greater source to sink ratio during grain ripening as measured by LAD/spikelet and dry matter production/spikelet which showed positove correlations with the grain ripening ratio. New plant type (NPT) line showed the lowest grain yield owing to the small sink size and the low grain filling ratio which seemed to have resulted from the abundant occurrence of weak-strength spikelets. The weak sink strength, in turn, seemed to have suppressed photosynthesis during the grain ripening stage.