• Journal of Nutrition and Health
• /
• 제32권4호
• /
• pp.369-375
• /
• 1999

Hyperthroidism in known to alter the activity of a number of enzymes involved in the catabolism of histidine to CO2. 10-Formyltetrahydrofolate dehydrogenase(EC 1.5, 1.6, 10-formyl-THE dehydrogenase) catalyzes the NADP-dependent conversion of 10-formyltetrahydrofolate to tetrahydrofolate and CO2. In previous studies, 10-formyl-THF dehydrogenase purified from rat and pig liver was coidentified with the cytosolic folate-binding protein. In this study, we investigated the effects of feeding thyroid powder (TP) and thiouracil(TU) on the folate-binding properties of 10-formyl-THE dehydrogenase, the uptake of an injected dose of [3H] folate, and the metabolism of labeled folate to pteroylopoly-${\gamma}$-glutamate in rat liver. The initial hepatic uptake(24hr) of the labeled folate dose was higher in TU-rats and slightly higher in TP-rats in controls. With longer time periods, decreased hepatic uptake of labeled folate was observed in TP-animals compared to euthroid animals, and high levels of hepatic uptake of labeled folate were maintained in TU-animals. This data shows that high levels of thyroid hormone decreased the retention of folate in rat liver. Folate polygutamate chain length was shorter in TU-rats than controls, which suggests that thyroid states do not affect the ability to synthesize pteroylpolyglutamates and that folate polyglutamate might be modulated by altered folate pool size. The ability of 10-formyl-THE dehydrogenase to bind folate in rat liver was similar in both TP-and TU-rats although dehydrogenase activity was changed by thyroid sates.

• 생약학회지
• /
• 제36권1호통권140호
• /
• pp.17-20
• /
• 2005

We previously reported that the exogenous administration of cumambrin A, a sesquiterpene lactone from the dried flowers of Chrysanthemum boreale Makino has a pharmacological effect on normalization of blood pressure in the spontaneously hypertensive rats (SHR). In the present study, we further investigated the effect of cumambrin A on the relaxation of phenylephrine-induced precontracted rat aortic artery rings. The potency of cumambrin A was than compared to verapamil, a well known $Ca^{2+}-channel$ blocker. The results demonstrate that the isolated rat aortic arteries are relaxed to basal tension at a concentration of $5{\times}10^{-5}\;M$ cumambrin A treatment. The results also show that the phenylephrine-induced contraction is inhibited by a pretreatment of cumambrin A. Co-treatment of cumambrin A and verapamil showed a strong synergetic effect on the relaxation of rat aortic artery rings. Thus, these data demonstrate that cumambrin A is a potent relaxant of rat aortic smooth muscle and suggest that cumambrin A modulates intracellular or extracellular $Ca^{2+}$ mobilization.

• 생약학회지
• /
• 제16권2호
• /
• pp.93-98
• /
• 1985

This investigation was performed to study the effect of Ginseng water extract on the cardiac sarcolemma $Na^+,\;K^+-ATPase$ activity of rat hearts. The Ginseng water extract (100mg/kg/day) was administered orally to Sprague-Dawley rats for one, four and seven days. The fragment of sarcolemma was prepared by the method of Matsui and Erdmann and the $Na^+,\;K^+-ATPase$ and $Mg^{++}-ATPase$ activity were measured by the method of Martins and Doty. $Na^+,\;K^+-ATPase$ activity in the rat heart treated with Ginseng water extract for 1 day was not significantly different from control value, but the activity was decreased by 13.4% in the rat heart treated for 4 days and was decreased by 20.4% in the 7 days treated group. $Mg^{++}-ATPase$ activity in the rat treated with ginseng water extract was similar to control value. It may be concluded that chronic administration of Ginseng may inhibit the $Na^+,\;K^+-ATPase$ enzyme activity, but single administration may not inhibit the activity.

• 동의생리병리학회지
• /
• 제19권5호
• /
• pp.1330-1336
• /
• 2005

This study was carried out to investigate the motor activity and glucose transport and metabolism of Gaewool-Whadam-Jian(GWJ) in rat gastro-intestinal tract. The motor activity of the rat gastro-intestinal tract has been investigated by means of measuring barium sulfate passage degrees. Atropine treatment significantly delayed barium sulfate transit, and GWJ pretreatment increased intestinal motor activity, but not significant. GWJ administration showed no toxicity to kidney and liver. Transport and metabolism of glucose were studied in everted sac of rat small intestine with incubation under several conditions. The transport and metabolism of glucose were greater at jejunum than ileum. So, everted jejunum of rat were used to study the effect of GWJ. When GWJ were treated, the concentration of glucose were higher than untreated group. This result was thought to be influenced by the glucose in GWJ. When 2, 4 dinitrophenol and phlorizin were treated, the transport and metabolism of glucose were decreased, but GWJ treated together, the concentration of glucose in serosal solution increased. Gastric juice secretion and total acidity significantly decreased by administration of GWJ through duodenum region. The mechanism of effect of GWJ was still unidentified, Dut through continuous investigation, the effect of GWJ should be investigated.

• Applied Microscopy
• /
• 제15권1호
• /
• pp.59-70
• /
• 1985

Morphogenesis of rat retina was studied by light and electron microscope from day 14 of gestation to 55 days after birth. The results indicate as follows: 1. At the outer border of the neuroblastic layer at the 14th day of gestation, cells she wed active mitotic figures which result in the increases of thickness and differentiations of this layer. 2. At birth, rat retina is still in a premature state. But, it is begining to approach its adult condition in appearance till the 9th postnatal day. Particulary photosensitive cells are fully developed by the 14th postnatal day, so they are functional from now on. 3. It is observed that the pigment epithelium begins differentiation at the fetal period, but is not functional urtil birth 4. The pigment epithelium differentiates earlier than the neuroblastic layer. It is suggested that these two layers are so closely associated that the pigment epithelium takes part in the differentiations of the neuroblastic layer. In conclusion, rat retina is differentiated soon after the optic cup formation before the 14th day of gestation, but even new born rat retina is not functional, and then it has function as photoreceptors coincided with the eye opening.

• Reproductive and Developmental Biology
• /
• 제29권4호
• /
• pp.229-234
• /
• 2005

Methods for activation of reconstructed oocytes were examined for the production of nuclear transfer (NT) rat embryos using fetal neural stem cells as donor. Neural stem cells were isolated from Day 14.5 rat fetuses, and the oocytes for recipient cytoplasm were recovered from 4-week old Sprague Dawley rats. After enucleation and nuclear injection, the reconstructed oocytes were immediately exposed to activation medium consisting of 10 mM $SrCl_2$ for 4 h (immediate activation after injection; IAI), or cultured in vitro for $2\~3$ h before activation treatment (injection before activation; IBA). Pre-activated oocytes were also used for NT to test reprogramming potential of artificially activated oocytes. The oocytes were grouped as IIA (immediate injection after activation) and ABI (activation $2\~3$ h before injection). Following NT, the oocytes were cultured in vitro. Development of the NT embryos was monitored at 44 and 119 h after activation. The embryos in groups IAI, mA, and IIA were cleaved to the 2-cell stage at the rates of $36.6\%\;(15/41),\;39.5\%\;(17/43)\;and\;46.3\%$ (25/54), respectively. However, in the ABI group, only one embryo ($1.8\%$, 1/55) was cleaved after activation. After in vitro culture, two NT embryos from IAI group had developed to the morula stage $(4.9\%\cdot2/41)$. However, no morula or blastocyst was obtained in the other groups. These results suggest that immediate activation after injection (IAI) method may be used for the production of rat somatic cell NT embryos.

• Journal of Ginseng Research
• /
• 제33권4호
• /
• pp.283-293
• /
• 2009

Ginsenosides, one of the most well-known traditional herbal medicines, are used frequently in Korea for the treatment of cardiovascular symptoms. The effects of ginseng saponin on ischemia-induced isolated rat heart were investigated through analyses of hemodynamic changes including perfusion pressure, aortic flow, coronary flow, and cardiac output. Isolated rat hearts were perfused and then subjected to 30 min of global ischemia followed by 60 min of reperfusion with modified Kreb's Henseleit solution. Myocardial contractile function was continuously recorded. Ginseng saponin administered before inducing ischemia significantly prevented decreases in perfusion pressure, aortic flow, coronary flow, and cardiac output. The ginseng saponin administered group significantly recovered all of the hemodynamic parameters, except heart rate, after ischemia-reperfusion (I/R) compared with ischemia control. The intracellular calcium ($[Ca^{2+}]_i$) content in rat neonatal cardiomyocytes was quantitatively determined. Administration of ginseng saponin significantly prevented $[Ca^{2+}]_i$ increase that had been induced by simulated I/R in vitro (p<0.01) in a dose-dependent manner, suggesting that the cardioprotection of ginseng saponin is mediated by the inhibition of $[Ca^{2+}]_i$ increase. Overall, we found that the administration of ginseng saponin has cardioprotective effects on the isolated rat heart after I/R injury. These results indicate that ginseng saponin has distinct cardioprotective effects in an I/R-induced rat heart.

• 한방안이비인후피부과학회지
• /
• 제28권4호
• /
• pp.41-50
• /
• 2015

Objectives : 선태는 아토피 피부염에서 소양증 완화를 위해 사용되고 있다. 본 연구에서는 면역계 및 신경계 손상을 일으킨 rat model에서 선태 추출물이 소양증 완화에 효과가 있는지 알아보고자 한다.Methods : 출생 48시간 이내의 rat을 대상으로, capsaicin(50 mg/kg)을 피하 투여하였다. 임의로 선정된 12마리의 실험군에 3주 동안 선태 추출물(0.5g/kg)을 매일 경구 투여하였다. 이후 scratching behavior 와 dermatitis score를 측정하였다.Results : 선태 투여군과 대조군에서 scratching number 와 dermatitis score의 차이가 없었다.Conclusions : 위의 결과로부터 capsaicin으로 유발한 아토피 피부염 rat model에서 선태의 소양증 완화 효과가 없다는 것을 알 수 있었다. 아토피 피부염의 효과적인 치료를 위해 면역계 뿐만 아니라 신경계 손상 회복시키는 약물을 찾기 위한 더 많은 연구가 필요할 것으로 생각된다.

• 대한전자공학회논문지TC
• /
• 제46권2호
• /
• pp.147-151
• /
• 2009

본 논문에서는 주파수 측정기의 핵심 소자이며 위상 비교 방향 탐지기의 핵심 소자인 위상 변별기를 설계하였다. Microwave Frequency대역 분류를 기준으로 하여 C-Band의 주파수 신호를 처리하는 광대역 Correlator를 설계하였다. 위상 번별기를 구성하는 광대역 2단 2way Power Divider를 설계하였으며, $180^{\circ}$ Metamaterial Hybrid Rat-Race Coupler와 $90^{\circ}$ Hybrid Coupler를 설계하여, 일반적인 위상변별기와 비교하여, Compact하며, 광대역인 특성을 얻을 수 있었다. 위상 변별기의 구성은 광대역 소자를 사용하였으며 그 외 Phase를 맞추기 위한 Delay Line을 구성하였다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
• /
• pp.514-515
• /
• 2008

Low level laser therapy has various therapy effects. This paper performed the basic study for developing the Low Level Laser Therapy Equipment for medical treatment. The apparatus has been fabricated using the laser diode and microprocessor unit. This equipment was fabricated using a micro-controller and a laser diode, and designed to enable us to control light time, frequency and so on. In this study, the designed device was used irradiation to find out how 850 nm laser diode affected the cell proliferation of RAT bone-marrow cells. Experiment was performed to irradiation group and non-irradiation group for Rat bone marrow cells. MTT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590 nm transmittance of micro plate reader. As a result, the cell increase of Rat bone marrow cells was verified in irradiation group as compared to non-irradiation group. The fact that specific wavelength irradiation has an effect on cell vitality and proliferation is known through this study.