• Applied Microscopy
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• v.39 no.3
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• pp.261-266
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• 2009

This study aim to disclose a possible mechanism for the neuronal cell death induced by peripheral nerve injury following a spinal nerve ligation (SNL) as a neuropathic pain model. Male Sprague-Dawley rats (270~290 g) were used for this study. Pain threshold was evaluated for their response to mechanical (von Frey hairs) stimuli 1, 3, and 7 days after a tight ligation of L5 ventral ramus. In control group, the small ganglion cells were strongly stained with routine toluidine blue (TB), whereas the large ganglion cells showed a little bit weak stainity. Each large ganglion cell is surrounded by perineuronal satellite cells. In experimental groups, small ganglion cells showing apparent degenerative changes increased on 1 day, and showed a peak in degenerative cell number at 3 days group, and decreased gradually at 7 days group. We also found a small number of large-sized ganglion cells showing mild degenerative changes. However their satellite cells ware relatively intact with no typical findings throughout this experiment. Under the electron microscope, small ganglion cells showed various stage and typical features of the dark degeneration including mitochondrial swelling.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.139-144
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• 2014

This study examined the efficacies of Cynanchum wilfordii and Phlomis umbrosa extracts on serum insulin like growth factor-I (IGF-I) and bone growth by raising rats in vivo. C. wilfordii and P. umbrosa extracts significantly increased serum IGF-I by 42% and 22% than the control, respectively. Treatment with ${\alpha}$-amylase when manufacturing these extracts remarkably increased the concentration of IGF-I by 63% and 36% above the control, respectively. This meant that these extracts, especially ${\alpha}$-amylase treated extracts, maintained a higher level of IGF-I secretion in the treated groups. In addition, increases of 6% in femur length were found after 8 weeks of oral administration with these extracts. These results indicate that C. wilfordii and P. umbrosa extracts have beneficial effects on bone growth via IGF-I.

• Korean Journal of Animal Reproduction
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• v.15 no.1
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• pp.41-47
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• 1991

The ability of fertilization in vitro and subsequent development of superovulated oocytes was assessed in a controlled environment using an in vitro fertilization technique. The in vitro fertilization percentage of oocytes with cumulus mass declined significantly(P<0.05) with increased doses from 4~10 to 16~40IU of PMSG for superovulation. However, the porportion of polyspermic penetration varied from 2.3 to 9.7% and there was no significant difference between treatments in incidence of polyspermy. When morphologically normal ova with cumulus mass were cultured for 66~72h in a plastic mini-straw to undergo fertilization in vitro, the mean percentage of embryos developed to 2-16 and 4-16cell stage was 61.8 and 17.6%; it was slightly(P<0.05) superior to the corresponding results from petri dish. A total of 52 two-cell embryos fertilized in a mini-straw were transferred to seven pseudopregnant rat. Among these recipients, two normal young were born from one recipient which received a total of six embryos. These results suggest that superovulated oocytes are proportionately less competent than normally ovulated oocytes to undergo fertilization in a controlled environment using an in vitro fertilization technique. Also, a plastic mini-straw designed was slightly superior to petri dish as a culture vessel for fertilization and embryo development in vitro.

• Korean Journal of Animal Reproduction
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• v.20 no.3
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• pp.251-258
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• 1996

This study was designed to evaluate the potential inhibitory effects of glucose (5.56 mM vs. 0 mM) and/or phosphate (potassium phosphate, 1.19 mM vs. 0 mM) on the in vitro devel-opment of rat 8-cell embryos (n=345 embryos from 36 mature rats). Evaluation of embryos at 48 h for developmental stage (STG) indicated that 37% (31/84), 70% (64/91), 69% (59/85), and 77% (67/85) developed to the blastocyst stage in media with glucose+phosphate, glucose only, phosphate only, and no glucose or phosphate, respectively. Embryo development (2.90${\pm}$0.097 for STG) in medium with glucose + phosphate was significantly reduced (P<0.001), while no significant differences were observed between all other media (3.4~3.5${\pm}$0.093-0.097 for STG). Evaluation of embryos for final cell number (FCN) indicated that the greatest number of cells (nuclei) resulted in medium with glucose alone (29.3${\pm}$0.97 cells, P<0.001). No significant differences were observed for FCN for the remaining three media (l7.5${\pm}$1, 04 cells, 18.6${\pm}$1.Ol cells, and 19.8${\pm}$1.01 cells for glucose+phosphate, phosphate only, and no glucose or phosphate, respectively). Our results suggest that glucose and phosphate together exert an inhibitory effect on 8-cell rat embryo development, while glucose alone was beneficial, yielding greater numbers of cells per embryo.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.323-330
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• 1998

Tetrahydroisoquinoline (THI) alkaloids can be considered as cyclized derivatives of simple phenylethylamines. Many of them, especially with 6,7-disubstitution, demonstrate a relatively high affinity for catecholamines. Present study examines the pharmacological action of limited series of THI, using rats' isolated atria and aorta. In addition, a $[^3H]$ prazosin displacement binding study with THI compounds was performed, using rat brain homogenates to investigate whether these probes have ?${\alpha}$-adrenoceptor affinity. We also compared the vascular relaxation potency of these probes with dobutamine. YS 49, YS 51, higenamine and dobutamine, concentration-dependently, relaxed endothelium-denuded rat thoracic aorta precontracted with phenylephrine (PE, 0.1 ${\mu}M$) in which $pEC_{50}$ were $5.56{\pm}0.32$ and $5.55{\pm}0.21$, $5.99{\pm}1.16$ and $5.57{\pm}0.34$, respectively. These probes except higenamine also relaxed KCl (65.4 mM)-contracted aorta. In isolated rat atria, all THIs and dobutamine increased heart rate and contractile force. In the presence of propranolol, the concentration response curves of YS 49 and YS 51 shifted to the right and resulted in $pA_2$ values of $8.07{\pm}0.84$ and $7.93{\pm}0.11$, respectively. The slope of each compound was not deviated from unity, indicating that these chemicals are highly competitive at the cardiac ?${\beta}-adrenoceptors$. YS 49, YS 51, and higenamine showed ?${\alpha)-adrenoceptor$ affinity in rat brain, in which the dissociation constant $(K_i)$ was 2.75, 2.81, and 1.02 ${\mu}M$, respectively. It is concluded, therefore, that THI alkaloids have weak affinity to ${\alpha)_1-adrenoceptor$ in rat aorta and brain, respectively, while these probes show relatively high affinity for cardiac ${\beta}-adrenoceptors$. Thus, these chemicals may be useful in the treatment of congestive heart failure.

• The Korean Journal of Pharmacology
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• v.31 no.2
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• pp.153-164
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• 1995

Sympathomimetic amines, especially ephedrine, are a major ingredient in proprietary medications for symptomatic treatment of upper respiratory infections. Their frequent uses can lead to occasional instances of abuse and habituation. The clinical symptoms of ephedrine abuse are similar to that of amphetamine psychosis and resemble closely that of schizophrenia. Because both amphetamine psychosis and schizophrenia are thought to be mediated primarily through the action on catecholamines, ephedrine-induced changes of the biogenic amines can be suspected. However, there were few studies about the central effects of ephedrine because of the milder central action than peripheral. Therefore, the present investigation was undertaken to elucidate the relations between the effects of single or repeated administration of ephedrine on the regional levels of biogenic amines in rat brain and ephedrine-induced CNS stimulation. The male Sprague-Dawley rats weighing $100{\sim}200\;g$ were used. After single or repeated administrations of ephedrine, blocks of tissue were obtained from frontal cortex, corpus striatum, hippocampus, thalamus, hypothalamus, substantia nigra and cerebellum. The concentration of biogenic amines(norepinephrine, epinephrine, dopamine, 5-hydroxytryptamine(5-HT)) and their metabolites (3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid(HVA), 5-hydroxyindoleacetic acid(5-HIAA)) were measured by means of high performance liquid chromatography-electrochemical detector(HPLC-ECD). The results obtained were as follows: 1) In the normal rat, the concentration of norepinephrine was the highest in hypothalamus. Dopamine, DOPAC and HVA were highest in corpus striatum, and 5-HT and 5-HIAA were highest in substantia nigra. Epinephrine was not detectable in any part of the brain tissue. 2) In a single administration of ephedrine, the concentration of DOPAC was decreased in corpus striatum. However, the other biogenic amines and their metabolites were not changed. 3) In repeated administration of ephedrine, the concentration of norepinephrine was decreased in all brain region checked. Dopamine was decreased in corpus striatum and substantia nigra and, increased in hypothalamus, and HVA was decreased in corpus striatum. 5-HT was decreased in all brain region except cerebellum and, 5-HIAA was decreased only in frontal cortex. The ratio of 5-HIAA/5-HT was increased in corpus striatum, thalamus, hypothalamus and substantia nigra. These data indicated that, although a single administration of ephedrine did not change the central neurotransmitters, repeated administration of ephedrine caused the decreases of norepinephrine and 5-HT in the most regions of brain, which may be responsible for the emergence of abnormal behavioral effect after ephedrine abuse.

• The Korean Journal of Pharmacology
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• v.20 no.2
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• pp.35-47
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• 1984

Contents of immunoreactive ${\beta}-endorphin$ and maximum of $^3H-morphine$ binding was measured in the rat midbrain homogenates from different subgroups at 24 hour interval over 24 hours. Animals were adapted to the light-dark cycle(L : D, 12: 12) or constant darkness (D : D, 12 : 12) for 3 weeks. After the adaptation, 0.5ml of physiologic saline or drug was administered twice a day for 2 weeks. A highly significant circadian rhythm with the peak$(94.8{\pm}7.7\;fmole/mg\;protein)$ at 06:00 and the nadir $(27.6{\pm}2.4\;fmole/mg\;protein)$ at 18:00 was observed in constant of group. Constant dark or treatment of reserpine, pargyline, imipramine, amphetamine and chlorpromazine modified the diurnal rhythm in the time of peak and nadir, shape, phase amplitude and 24 hour mean of ${\beta}-endorphin$ contents. Opiate receptor binding by $^3H-morphine$ also showed highly significant diurnal change in control and constant dark adapted rats. Statistical analysis by one-way analysis of variance and two-way analysis of variance indicates that the·re are highly significant differences between the diurnal change of ${\beta}-endorphin$ in control and those constant dark adapted and drug treated groups. However diurnal change of Maximum $^3H-morphine$ binding is closely related to the change of ${\beta}-endorphin$ contents. The results are interpreted with regard to the circadian rhythm of beta-endorphin contents, its modification by psychoactive drugs and possible mechanism of diurnal change of opiate receptor in brain.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.1
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• pp.7-15
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• 2004

Nitric oxide (NO) system has been implicated in a wide range of physiological functions in the nervous system. However, the role of NO in regulating the neural activity in the gustatory zone of nucleus tractus solitarius (NTS) has not been established. The present study was aimed to investigate the role of NO in the gustatory NTS neurons. Sprague-Dawley rats, weighing about 50 g, were used. Whole cell patch recording and immunohistochemistry were done to determine the electrophysiological characteristics of the rostral gustatory nucleus of the tractus solitaries and distribution of NO synthases (NOS). Neuronal NOS (nNOS) immunoreactivity was strongly detected along the solitary tract extending from rostral to caudal medulla. Resting membrane potentials of NTS neurons were $-49.2{\pm}2\;mV$ and action potential amplitudes were $68.5{\pm}2\;mV$ with a mean duration measured at half amplitude of $1.7{\pm}0.3\;ms$. Input resistance, determined from the response to a 150 ms, -100 pA hyperpolarizing current pulse, was $385{\pm}15\;M{\Omega}$, Superfusion of SNAP or SNP, NO donors, produced either hyperpolarization (68%), depolarization (5%), or no effect (27%). The hyperpolarization was mostly accompanied by a decrease in input resistance. The hyperpolarization caused by SNAP or SNP increased the time to initiate the first action potential, and decreased the number of action potentials elicited by current injection. SNP or SNAP also markedly decreased the number of firing neural discharges of the spontaneous NTS neural activity under zero current. Superfusion of L-NAME, a NOS inhibitor, slightly depolarized the membrane potential and increased the firing rate of NTS neurons induced by current injection. ODQ, a soluble guanylate cyclase inhibitor, ameliorated the SNAP-induced changes in membrane potential, input resistance and firing rates. 8-Br-cGMP, a non-degradable cell-permeable cGMP, hyperpolarized the membrane potential and decreased the number of action potentials. It is suggested that NO in the gustatory NTS has an inhibitory role on the neural activity of NTS through activating soluble guanylate cyclase.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.18 no.3
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• pp.44-54
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• 2005

Background and Objectives: Allergic contact dermatitis is a common environmental health issue and seriously affect the patient's quality of life. The more our environment industrialized, the number of material that could cause the allergic contact dermatitis has been increased, consequently the prevalence of allergic contact dermatitis has been increased. In oriental medicine, clinically Chogam-Tang has been used fur the treatment of allergic dermatitis, eczema, atopic dermatitis etc. The objective of this study is to investigate the effects of Chogam-Tang on allergic contact dermatitis Meterial and Methods: Fifteen Sprague-Dawley rats were divided into three groups: normal, control, experimental group. Control and experimental group were induced allergic contact dermatitis, by DNCB. Experimental group was orally administered the Chogam-Tang. Each group was observed after 24, 48 and 72 hours. Contact hypersensitivity assay, melanin-erythema measurement, pH measurement skin moisture measurement and biopsy were performed. Results: 1. In contact hypersensitivity assay, experimental group showed decreased ear swelling compared with control group at 48hours. 2. ln melanin measurement there was no difference in three groups. 3. In erythema measurement experimental group showed reduction at 48. 72 hours. 4. In pH measurement, experimental group and control group showed increase in pH but there was no statistical significance. 5. In skin moisture measurement, experimental group showed higher skin moisture level than control group at 24 hours and showed lower skin moisture level at 72 hours, but there was no statistical significance. 6. In biopsy, experimental group showed decrement of Iymphocyte as time goes by, and regeneration of keratin layer was increased compared with normal group. Conclusions: Chogam-Tang shows anti-inflammatory effect in biopsy, improves hydration levels of skin, decreases erythema level on allergic contact dermatitis.

• Archives of Plastic Surgery
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• v.34 no.2
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• pp.169-175
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• 2007

Purpose: $Allevyn^{(R)}$(Smith & Nephew, England) is a type of polyurethane foam material with good wound discharge absorption. $Acticoat^{(R)}$(Smith & Nephew, England) is a silver coated dressing material which is effective in infected wound. The purpose of this study is to compare the effects of dry gauze, $Acticoat^{(R)}$ and $Allevyn^{(R)}$ on infected full-thickness wound healing in rat. Methods: One hundred and twenty rats were divided into 3 groups: group I(dressing with dry gauze, n=40), group II(dressing with $Allevyn^{(R)}$, n=40), group III(dressing with $Acticoat^{(R)}$, n=40). A $15{\times}15mm$ square full-thickness wound was made on the dorsum and left open for 24 hours. The size of wound defects were measured each dressing changes. The histological evaluation was performed on the 3rd day, 7th day, 14th day, 21th day. Results: After the wound was left open for 24 hours, typical findings of bacterial infection was observed. After the 7th day, group III showed larger area of epithelialization, smaller defect size compared to those of two other groups. Complete replacement by fibrotic scar tissue was observed in group III with no signs of inflammation on the 14th day. By day 21, the average defect size in group III was decreased from initial 100% to 3.63%. while in group I and II, it was decreased to 62.66% and 53.62%, respectively. Conclusion: $Acticoat^{(R)}$ is an effective tool in the treatment of infected wound.