• The Korean Journal of Physiology and Pharmacology
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• v.12 no.1
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• pp.13-23
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• 2008

The aim of the present study was designed to establish comparatively the inhibitory effects of $D_1$-like and $D_2$-like dopaminergic receptor agonists, SKF81297 and R(-)-TNPA on the release of catecholamines (CA) evoked by cholinergic stimulation and membrane depolarization from the isolated perfused model of the rat adrenal medulla. SKF81297 $(30{\mu}M)$ and R-(-)-TNPA $(30{\mu}M)$ perfused into an adrenal vein for 60 min, produced great inhibition in the CA secretory responses evoked by ACh $(5.32{\times}10^{-3}\;M)$, DMPP $(10^{-4}\;M)$, McN-A-343 $(10^{-4}\;M)$, high $K^+$ $(5.6{\times}10^{-2}\;M)$, Bay-K-8644 $(10{\mu}M)$, and cyclopiazonic acid $(10{\mu}M)$, respectively. For the release of CA evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid, the following rank order of inhibitory potency was obtained: SKF81297>R-(-)-TNPA. However, R(+)-SCH23390, a selectve $D_1$-like dopaminergic receptor antagonist, and S(-)-raclopride, a selectve $D_2$-like dopaminergic receptor antagonist, enhanced the CA secretory responses evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid only for $0{\sim}4$ min. The rank order for the enhancement of CA release evoked by high $K^+$, McN-A-343 and cyclopiazonic acid was R(+)-SCH23390>S(-)-raclopride. Also, the rank order for ACh, DMPP and Bay-K-8644 was S(-)-raclopride > R(+)-SCH23390. Taken together, these results demonstrate that both SKF81297 and R-(-)-TNPA inhibit the CA release evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors and the membrane depolarization from the isolated perfused rat adrenal gland without affecting the basal release, respectively, but both R(+)-SCH23390 and S(-)-raclopride facilitate the CA release evoked by them. It seems likely that the inhibitory effects of SKF81297 and R-(-)-TNPA are mediated by the activation of $D_1$-like and $D_2$-like dopaminergic receptors located on the rat adrenomedullary chromaffin cells, respectively, whereas the facilitatory effects of R(+)-SCH23390 and S(-)-raclopride are mediated by the blockade of $D_1$-like and $D_2$-like dopaminergic receptors, respectively: this action is possibly associated with extra- and intracellular calcium mobilization. Based on these results, it is thought that the presence of dopaminergic $D_1$ receptors may play an important role in regulation of the rat adrenomedullary CA secretion, in addition to well-known dopaminergic $D_2$ receptors.

• The Korean Journal of Food And Nutrition
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• v.16 no.1
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• pp.36-45
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• 2003

It is known as that onion is antioxidation effect, antibiotic effect, blood pressure decreasing effect and reducing serum cholesterol levels. This research about effect that onion concentrate gets blood cholesterol levels and body composition. Subject was 17 adult men of hyperlipidemia. Age distribution of investigation subjects were average 49.4 years old by 40~56 years old, and average height and weight were 167.6cm and 75.5kg each, BMI was 26.9kg/$m^2$, and BMR was 1,460.6$\pm$87.5㎉, and AMC was 25.0$\pm$1.05cm, and BCM was 41.0$\pm$2.79cm. In the meantime, the body muscle was 53.7$\pm$3.7kg, and fat mass was 18.7$\pm$3.8kg, and intracellular fluid was 26.6$\pm$1.8kg, and extracellular fluid was 12.8$\pm$0.9kg. The % body fat was 24.6$\pm$3.8%, and fat distribution was 0.9$\pm$0.0%, and the obesity degree was 125.4$\pm$8.2%. Vegetables, seaweeds, fruits and juices increased by change of dietary life and greasy foods, instants, breads, rices etc. decreased or there was no change, fast foods and eggs were no change. Also, subject previewed that guidance about stress, smoking, drinking and beverage intake need. If compared the nutrient intake amount with before onion concentrate allowance, it was similar level almost without significant. Energy, calcium and riboflavin are lower than the RDA for koreans. After 3 months, the levels of plasma total cholesterol, triglycerides had decreased significantly : 15.0%, 31.2% respectively. And the HDL-cholesterol and LDL-cholesterol levels also showed a marked reduction of 6.8%, 8.7% respectively. Plasma lipid level change by onion concentrate supplement would can know that case of triglyceride more greatly than plasma cholesterol. The pH and Na+ level of plasma were low significant since 8 weeks after, and $K^{+}$ level increase significant. While $Ca^{++}$ level was low significant after 1 month, there was no change since 2 months after, but nC $a^{++}$ level was low significantly. Plasma $Mg^{++}$ level was no change and nM $g^{++}$ level was low significant after intake.e.e.e.e.e.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.236-243
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• 2023

Platelets act a fundamental role in primary- and secondary-hemostasis, however, platelet activation may cause thrombosis simultaneously. Therefore, control of platelet aggregation is crucial in preventing thrombosis-mediated diseases. Recently, the development of insect materials is attracting attention. Among the highly nutritious functional food sources, insects such as two-spotted cricket (Gryllus bimaculatus). Gryllus bimaculatus (G. bimaculatus) contains high protein and unsaturated fatty acids and has been registered as a food material September 2015 by the Ministry of Food and Drug Safety of Korea. In this study, we examined whether G. bimaculatus extract (GBE) inhibits platelet aggregation, intracellular calcium mobilization, thromboxane A₂ production and glycoprotein IIb/IIIa (integrin αIIb/β3) activation. We investigated whether GBE can regulate signaling molecules, such as 1, 4, 5-triphosphate receptor type I, extracellular signal-regulated kinase, cytosolic phospholipase A₂, mitogen-activated protein kinases p38, vasodilator-stimulated phosphoprotein, phosphatidylinositol-3 kinase, Akt, glycogen synthase kinase-3α/β, and SYK. Taken together, GBE is a potential therapeutic drug candidate to prevent platelet-related thrombosis and cardiovascular disease.

• The Korean Journal of Pharmacology
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• v.31 no.1 s.57
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• pp.63-74
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• 1995

It has been known that, during hypoxia, the adrenal medulla is activated to release catecholamines (CA) while hypoxia also inhibits high $K^+$ -induced CA secretion in the cultured bovine adrenal chromaffin cells. The present study was attempted to examine the effect of hypoxia on CA secretion evoked by chlinergic stimulation and membrane-depolarization from the isolated perfused rat adrenal glands and also to clarify its mechanism of action. For this purpose, using the isolated rat adrenal glands, the effects of hypoxia on CA release evoked by nicotinic ($N_1$) and muscarinic ($M_1$) receptor agonists, membrane-depolarizing agent, $Ca^{++}$-channel activator, intracellular $Ca^{++}$-releaser and ACh were determined. Experiments were carried out, perfusing Krebs solution pre-equilibrated with a gas mixture of 95% N_2$ and 5% $CO_2$. Hypoxia was maintained for $3{\sim}4$ hours through the experiments. Hypoxia gradually caused a time-dependent seduction in CA secretion evoked by DMPP ($100{\mu}M$), McN-A-343 ($100{\mu}M$), ACh (5.32 mM), Bay-K-8644 ($10{\mu}M$) and high $K^+$ (56 mM) respectively. How-ever, it did not affect CA secretion evoked by cyclopiazonic acid ($10{\mu}M$). Hypoxia itself also did fail to produce any influence on spontaneous secretory response of CA. These experimental results suggest that hypoxia depresses CA release evoked by both cholinergic stimulation and membrane-depolarization from the isolated rat adrenal medulla, and that this inhibitory activity may be due to the result of the direct inhibition of $Ca^{++}$ influx into the chromaffin cells without any effect on the calcium mobilization from the intracellular store.

• Journal of Chest Surgery
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• v.42 no.5
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• pp.588-596
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• 2009

Background: To clarify the effect of hypoxia on vascular contractility, we tried to show whether hypoxia induced the release of endothelium-derived relaxing factor (EDRF) and the nature of the underlying mechanism for this release. Material and Method: Isometric contractions were observed in rabbit aorta, and the released EDRF from the rabbit aorta was bioassayed by using rabbit denuded carotid artery. The intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) in the cultured rabbit aortic endothelial cells was recorded by a microfluorimeter with using Fura-2/AM. Hypoxia was evoked to the blood vessels or endothelial cells by eliminating the $O_2$ in the aerating gases in the external solution. Chemical hypoxia was evoked by applying deoxyglucose or $CN^-$. Result: Hypoxia relaxed the precontracted rabbit thoracic aorta that had its endothelium, and the magnitude of the relaxation was gradually increased by repetitive bouts of hypoxia. In contrast, hypoxia-induced relaxation was not evoked in the aorta that was denuded of endothelium. In a bioassay experiment, hypoxia released endothelium-derived relaxing factor (EDRF) and the release was inhibited by L-NAME or the $K^+$ channel blocker tetraethylammonium (TEA). In the cultured endothelial cells, hypoxia augmented the ATP-induced increase of the intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) and this increase was inhibited by TEA. Furthermore, chemical hypoxia also increased the $Ca^{2+}$ influx. Conclusion: From these results, it can be concluded that hypoxia might induce the release of NO from rabbit aortic endothelial cells by increasing $[[Ca^{2+}]_i$.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.3
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• pp.254-261
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• 2000

The present study has attempted to look into the mechanism of ras-induced carcinogenesis in a human epithelial cell system. Human epithelial cells immortalized with Ad12-SV40 hybrid virus were used to assess carcinogenic potential of the ras-oncogene. Cells transfected with pSV2-ras showed characteristics of cellular transformation. The transformation parameters such as cell density, soft-agar colony formation, and cell aggregation were significantly increased in the cells expressing ras oncoprotein. In addition, the duration required for the appearance of foci was shortened in the ras-transfected cells. Consistent with other reports, our results demonstrated an evidence that the ras-oncogene induced the cellular transformation of human epithelial cell system. When a high concentration of glucocorticoid was added into the media, transformation process was accelerated. It is speculated that glucocorticoid may provide an advantageous environment for the proliferation of the transformed cells. The induction of the intracellular free calcium concentrations following agonist treatment was significantly lower in the transformed cells than in the control cells. These effects were more manifested in the presence of extracellular cacium, indicating that the transformation process may alter the influx pathway of extracellular calcium. The induction of $IP_3$ following agonist treatment was also lower in the transformed cells than in the control cells. Thus, it is suggested that phospholipase C-coupled pathway was down-regulated in the process of the ras-induced transformation. While the levels of $TGF-{\beta}_1$ and PAI-2 mRNAs were decreased, the level of fibronectin mRNA was increased. The results indicate that mechanism of the ras-induced transformation may be associated with the altered expressions of growth regulatory factors. The present study demonstrates an evidence that the ras-induced cellular transformation may be associated with alteration of signal transduction and growth regulatory factors. The study will contribute to improve the understanding of molecular mechanism of epithelium-derived cancers including oral cancer.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.455-462
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• 2003

A study was conducted to determine the effects of feeding a diet containing no Ca supplement (limestone) during the late finishing period on growth, marbling and serum 1,25-dihydroxy vitamin $D_3$ level in Korean native cattle. Twenty-four steers (20${\sim}$24 mo of age) were divided into two groups of 12 each: one group assigned to a control diet (concentrates containing 2.5% limestone) and the other to a diet containing no calcium supplement. They were allowed to have free access to diets (concentrates and orchard grass hay) and water during the entire feeding period (223 d). Serum $Ca^{2+}$, Ca and P concentrations were not influenced by diets, but serum 1,25-dihydroxy vitamin $D_3$ concentrations determined 2 or 6 mo after the beginning of feeding the experimental diets were higher (P<0.01) in steers fed the diet without Ca supplement than in those fed the control diet (78.3 vs 51.7 and 80.3 vs 51.1 pg/mL, respectively). Steers fed the diet without Ca supplement tended to have a higher intake of concentrates, but a lower intake of hay, compared to those fed the control diet. Average daily gain was higher (P<0.05) in steers fed the diet without Ca supplement than in those fed the control diet. Feeding the diet without Ca supplement remarkably (P<0.01) increased the marbling score (5.1 vs 2.2) and the muscle (M. longissimus dorsi) fat content (10.2 vs 6.7%) with a concomitant decrease in moisture content (67.6 vs 70.4%), compared to feeding the control diet. Ribeye area was increased (77.2 vs 82.8 $cm^2$) with the diet without Ca supplement, compared to the control diet (P<0.05). Meat color, pH and water-holding capacity in longissimus muscle were not different between the two groups. The Warner-Brazler Shear (WBS) force of the longissimus muscle was slightly (P=0.08) lower in steers fed the diet without Ca supplement than in steers fed the control diet (2.9 vs 3.2 kg/1.27-cm diameter core). Sensory evaluation showed that feeding the diet without Ca supplement slightly (P<0.05) improved tenderness (4.9 vs 4.5) and flavor (4.9 vs 4.6), compared to feeding the control diet, but juiciness was not affected by diets. Results showed that deletion of Ca supplement from finishing diets is beneficial, increasing growth and marbling partly through an increased energy intake and induced 1,25-dihydroxy vitamin $D_3$ synthesis that may increase intracellular $Ca^{2+}$ concentration and in turn fat synthesis.

• Radiation Oncology Journal
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• v.16 no.4
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• pp.367-375
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• 1998

Purpose : Xerostomia is a complication met by almost all patients who have radiotherapy for cancers of head and neck. Many studies for prevention of xerostomia will be necessary. Radiation-induced acute response of salivary glands has been defined as interphase death or apoptosis. Increased intracellular calcium level have an important role in radiation-induced apoptosis. Calcium channel blocker may prevent radiation-induced apoptosis of salivary glands. This study was designed to evaluate the effectiveness of diltiazem known as calcium channel blocker and pentoxifylline with inhibition of inflammatory response on the apoptosis as an acute response of radiation in rat salivary glands. Materials and Methods : Sprague-Dawley rats with about body weight 200-250 g were divided into 5 study groups : control, radiation alone, diltiazem with radiation, pentoxifylline with radiation, and diltiazem and pentoxifylline with radiation. The diltiazen and pentoxifylline were injected intraperitoneally 20 mg/kg and 50 mg/kg, 30 and 20 mimute before irradiation. respectively. Irradiation was given with a 4 MV linear accelerator. The 1600 cGy of radiation was delivered in a single fraction through a single anterior portal encompassing the entire neck. After 24 h of irradiation, rats were sacrificed and parotid and submandibular glands were removed and stained with hematoxylin and eosin. The quantification of apoptosis was performed by microscopic examination of stained tissue sections at a magnification of 200X and the percentage of apoptotic cell was calculated. Results : On parotid glands, the percentage of apoptosis by radiation alone, diltiazem with radiation, pentoxifylline with radiation, and diltiazem and pentoxifylline with radiation were 1.72$\%$ (8.35/486), 0.64$\%$ (2.9/453), 0.23$\%$ (1.2/516), and 0.28$\%$ (1.1/399), respectively. The apoptosis was markedly reduced in the groups receiving drugs compared with groups receivinge, radiation alone (p<0.05). In serous cell of submandibular glands, the percentages of apoptosis of radiation alone, diltiazem with radiation, pentoxifylline with radiation, and diltiazem and pentoxifylline with radiation were 1.94$\%$ (l1/567), 0.34$\%$ (1.9/554), 0.28$\%$ (1.8/637), and 0.22$\%$ (1.3/601), respectively. In the mucus cell of submandibular glands, the percentages of apoptosis were 0.92$\%$ (5.1/552), 0.41$\%$ (2.5/612), 0.29$\%$ (1.3/455), and 0.18$\%$ (1.0/562), respectively. The apoptosis was markedly reduced in the serous glands (p<0.05), but there was no difference in development of apoptosis in each group of mucus gland. Conclusion : These results suggest that radiation-induced apoptosis of serous cells of salivary glands may be decreased by diltiazem and pentoxifylline administration.

• Journal of Chest Surgery
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• v.37 no.3
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• pp.210-219
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• 2004

Extracellular $K^{+}$ concentration ([ $K^{+}$]$_{0}$ ) can be increased within several mM by the efflux of intracellular $K^{+}$. To investigate the effect of an increase in [ $K^{+}$]$_{0}$ on vascular contractility, we attempted to examine whether extracellular $K^{+}$ might modulate vascular contractility, endothelium-dependent relaxation (EDR) and intracellular $Ca^2$$^{+}$ concentration ([C $a^2$$^{+}$]$_{i}$ ) in endothelial cells (EC). We observed isometric contractions in rabbit carotid, superior mesenteric, basilar arteries and movse aorta. [C $a^2$$^{+}$]$_{i}$ was recorded by microfluorimeter using Fura-2/AM in EC. No change in contractility was recorded by the increase in [ $K^{+}$]$_{0}$ from 6 to 12 mM in conduit artery such as rabbit carotid artery. whereas resistant vessels, such as basilar and branches of superior mesenteric arteries (SMA), were relaxed by the increase. In basilar artery, the relaxation by the increase in [ $K^{+}$]$_{0}$ to from 1 to 3 mM was bigger than that by the increase from 6 to 12 mM. In contrast, in branches of SMA, the relaxation by the increase in [ $K^{+}$]$_{0}$ to from 6 to 12 mM is bigger than that by the increase from 1 to 3 mM. $Ba^2$$^{+}$ (30 $\mu$M) did not inhibit the relaxation by the increase in [ $K^{+}$]$_{0}$ from 1 to 3 mM but did inhibit the relaxation by the increase from 6 to 12 mM. In the mouse aorta without the endothelium or treated with $N^{G}$_nitro-L-arginine (30 $\mu$M), nitric oxide synthesis blocker, the increase in [ $K^{+}$]$_{0}$ from 6 to 12 mM did not change the magnitude of contraction induced either norepinephrine or prostaglandin $F_2$$_{\alpha}$. The increase in [ $K^{+}$]$_{0}$ up to 12 mM did not induce contraction of mouse aorta but the increase more than 12 mM induced contraction. In the mouse aorta, EDR was completely inhibited on increasing [ $K^{+}$]$_{0}$ from 6 to 12 mM. In cultured mouse aorta EC, [C $a^2$$^{+}$]$_{i}$ , was increased by acetylcholine or ATP application and the increased [C $a^2$$^{+}$]$_{i}$ , was reduced by the increase in [ $K^{+}$]$_{0}$ reversibly and concentration-dependently. In human umbilical vein EC, similar effect of extracellular $K^{+}$ was observed. Ouabain, a N $a^{+}$ - $K^{+}$ pump blocker, and N $i^2$$^{+}$, a N $a^{+}$ - $Ca^2$$^{+}$ exchanger blocker, reversed the inhibitory effect of extracellular $K^{+}$. In resistant arteries, the increase in [ $K^{+}$]$_{0}$ relaxes vascular smooth muscle and the underlying mechanisms differ according to the kinds of the arteries; $Ba^2$$^{+}$-insensitive mechanism in basilar artery and $Ba^2$$^{+}$ -sensitive one in branches of SMA. It also inhibits [C $a^2$$^{+}$]$_{i}$ , increase in EC and thereby EDR. The initial mechanism of the inhibition may be due to the activation of N $a^{+}$ - $K^{+}$pump. activation of N $a^{+}$ - $K^{+}$pump.p.p.p.

• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.1-9
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• 2011

Differentially Expressed Gene (DEG) was obtained from Differential Display Reverse Transcription (DDRT)-PCR using Annealing Control Primer (ACP) to search and clone genes related to developmental stages of Sebastes inermis. By using 120 ACPs, the nucleotide sequences obtained from 16 DEGs showing higher expression in 6-month-old skeletal muscle than 18-month-old ones and from 22 DEGs displaying stronger expression in 18-month-old than 6-month-old were analyzed and BLAST was conducted. The results identified that DEGs shared 69~95% homology with genes of parvalbumin (PVALB), nucleoside diphosphate kinase (NDK) B, tropomyosin (TPM), troponin I (TnI), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), muscle-type creatine kinase (CKM2), small EDRK-rich factor 2 (SERF2), adenosine monophosphate deaminase (AMPD), Trimeric intracellular cation channel type A (TRICA), Rho GTPase-activating protein 15 (ARHGAP15), S-formylglutathione hydrolase (Esterase D; ESD), heat shock protein 70 (hsp70), type 1 collagen alpha 2 (COL1A2), glutathione S-transferase, Mid1-interacting protein 1 (Mid1lip1), myosin light chain 1 (MYL1), sarcoplasmic/endoplasmic reticulum calcium ATPase 1B (SERCA1B), and ferritin heavy subunit (FTH1). Expression pattern by developmental stage of DEG14 and PVALB exhibiting strong expression in 6-month-old skeletal muscle was investigated using real time PCR. Expression was reduced as Sebastes inermis grew. Expression of PVALB gene was extremely low after 6 months of age. Expression of CKM2 showed higher expression in 18-month-old skeletal muscle than in 6-month-old muscles, and increased continuously until 4 years old, after which CKM2 expression became gradually reduced. By analysis of tissue-specific expression patterns of DEG, DEG14 was expressed mainly in skeletal muscle, liver, kidney and spleen tissues, whereas PVALB expression was expressed in skeletal muscle and kidney, but not in liver and spleen tissues. CKM2 was expressed in skeletal muscle, kidney, and spleen tissues, but not in liver tissues. PVALB gene was composed of 110 amino acids, which constituted 659 bp nucleotides. The results reported here demonstrate that the expression patterns of parvalbumin and CKM2 could be used as molecular markers for selecting fishes exhibiting fast growth.