• Korean Journal of Microbiology
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• v.25 no.2
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• pp.94-102
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• 1987

Rat liver LDH A-cDNA has been isolated from a .lambda.gt11-rat lover cDNA library and partially characterized. The size of the isolated rat liver LDH A-cDNA if shown to be 1.6Kb and restriction enzyme sites for the rat liver LDH A-cDNA are also mapped. 682-nucleotide sequence coding for 3'-end of rat liver LDH A-cDNA has been analyzed and compared to the nucleotide sequence of the same region of rat $C_6$-glioma cell LDH A-cDNA which has been cloned from the hormonally stimulated cell cultures. The result shows that 177 nucleotide sequences coding for the C-terminal 59-amino acids are identical but 505 nucleotide sequences of 3'-nontranslated region of the two LSH A-cDNA exhibit characteristic differences in thier nucleotide sequences. Computer analysis for the folding structures for 3'-end 400 nucleotide sequences of the two LDH A-cDNA shows a possibility implying that the two LDH A-mRNAs isolated from different tissues of rats may have different half life and therefore their translational efficiency may be different. It has been previously demonstrated that isoproterenol stimulated rat $C_6$ -glioma cell cultures produce LDH A-mRNA showing 2 to 3-fold longer half life in comparison to that of noninduced LHD A-mRNA. The result therefore support for the idea that hormonally stimulated rat $C_6$-glioma cells may produce LDH A-mRNA containing different nucleotide sequences at the 3'-end nontranslated region by which the hormonally induced LDH A-mRNA could have more stable secondary mRAN structure in comparison to that of noninduced LDH A-mRNA.

• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.436-442
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• 2001

Neuropeptide such as calcitonin gene-related peptide and substance P may mediate neurogenic inflammation, but little is known about the regulation of neuropeptide release from rat spinal cord. Eugenol has been reported to reduce odontogenic pain and is known to have a structure similar to capsaicin, a potent stimulant of certain nociceptors. This study was done to examine the effect of capsaicin and eugenol on immunoreactive calcitonin gene-related peptide (iCGRP) release from rat spinal cord and whether eugenol regulates capsaicin-sensitive release of iCCRP or it evokes capsaicin-sensitive release of iCGRP. The dor-sal half of rat lumbar spinal cord was chopped into 200$\mu$m slices. They were superfused (500$\mu$l/min) in vitro with an oxygenated Kreb's buffer. The EC$_{50}$ of capsaicin on iCGRP release was measured. Eugenol (600$\mu$M and 1.2mM) and vehicle (0.02% 2-hydroxyl-$\beta$-cyclodextrin) were administered prior to stimulation of rat lumbar spinal cord with capsaicin. The amount of iCGRP release from rat lumbar spinal cord was measured by radioimmunoassay. The results were as follows : 1. iCGRP release from rat lumbar spinal cord was dependent on concentration of capsaicin. The EC$_{50}$ of capsaicin on iCGRP release was 3$\mu$M. 2. In the vehicle treated group, capsaicin (3$\mu$M) evoked a 14-fold increase over basal iCGRP level. 3. Administration of 600$\mu$M and 1.2mM eugenol evoked a 2.2-fold increase and a 2.3-fold increase over basal iCGRP level respectively. 4. Administration of 600$\mu$M and 1.2mM eugenol increased capsaicin evoked release of iCGRP by more than 50%. These results indicate that eugenol evoke CGRP release from central nervous system and potentiate the pain-inducing action of capsaicin on it.

• Korean Journal of Pharmacognosy
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• v.25 no.3
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• pp.238-248
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• 1994

The hypoglycemic and metabolic effects of Commelina communis L. extract were investigated in alloxan induced diabetic rats. The increased blood glucose level in the diabetic rats was significantly reduced and the loss of body weight was recovered with the treatment of the plant protein fractions($30{\sim}70%$ ammonium sulfate precipitates). Administration of the plant protein fractions elicited the significant increase of glucose-6-phosphate dehydrogenase (G-6-P DH) activity and liver weight which were decreased in the diabetic rat liver. G-6-P DH was partially purified from extract- or insulin-treated diabetics, diabetic control, and normal rat liver and studied for the biochemical properties. The $K_m$ value(9.002 mM) of diabetic rat liver enzyme was greatly higher than that (0.033 mM) of normal enzyme indicating the affinity of enzyme for the substrate was significantly reduced in the diabetic rat liver. This reduced affinity of enzyme for the substrate in the diabetic rat was recovered in the extract- or insulin-treated rat liver enzyme having 0.164 or 0.208 mM of their $K_m$ values, respectively. Although there was no significant difference in the optimum pH(6.0) and optimum temperature($37^{\circ}C$) of enzyme among the experimental groups, the dependence of their activities on pH appeared to be slightly resistant in the extract- or insulin-treated group compared to the diabetic group. In order to investigate the antigenicity of rat liver enzyme among experimental groups, enzyme-linked immunosorbent assay was carried out by using anti-G-6-P DH anti-serum. Absorbance(0.102) shown in the normal rat liver was reduced even below zero in the alloxan-diabetic rat liver, but increased again in the extract- or insulin-treated rat liver(0.096 or 0.118, respectively). The result of this study suggested that G-6-P DH may be used as a marker enzyme to diagnose and to indicate the progress of the diabetics, and the hypoglycemic effect of the extracts of Commelina communis L. was certainly associated with action or mode of G-6-P DH on the rat liver.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.5
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• pp.471-479
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• 1999

The Kv channel activity in vascular smooth muscle cell plays an important role in the regulation of membrane potential and blood vessel tone. It was postulated that increased blood vessel tone in hypertension was associated with alteration of Kv channel and membrane potential. Therefore, using whole cell mode of patch-clamp technique, the membrane potential and the 4-AP-sensitive Kv current in cerebral arterial smooth muscle cells were compared between normotensive rat and one-kidney, one-clip Goldblatt hypertensive rat (lK,lC-GBH rat). Cell capacitance of hypertensive rat was similar to that of normotensive rat. Cell capacitance of normotensive rat and 1K,lC-GBH rat were $20.8{\pm}2.3$ and $19.5{\pm}1.4$ pF, respectively. The resting membrane potentials measured in current clamp mode from normotensive rat and 1K,lC-GBH rat were $-45.9{\pm}1.7$ and $-38.5{\pm}1.6$ mV, respectively. 4-AP (5 mM) caused the resting membrane potential hypopolarize but charybdotoxin $(0.1\;{\mu}M)$ did not cause any change of membrane potential. Component of 4-AP-sensitive Kv current was smaller in 1K,lC-GBH rat than in normotensive rat. The voltage dependence of steady-state activation and inactivation of Kv channel determined by using double-pulse protocol showed no significant difference. These results suggest that 4-AP-sensitive Kv channels playa major role in the regulation of membrane potential in cerebral arterial smooth muscle cells and alterations of 4-AP-sensitive Kv channels would contribute to hypopolarization of membrane potential in 1K,lC-GBH rat.

• Proceedings of the Ginseng society Conference
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• 1990.06a
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• pp.58-64
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• 1990

The effects of ginseng saponins, G-Rbl and G-Rc on the rat liver LDH A-gene transcnptional activity was investigated during pro-replicative phase of rat liver after partial hepatectomy. Changes in LDH A-mRNA levels in regenerating rat liver after intraperitoneal administrations of G-Rbl of G-Rc were tested by slot blot hybridization methods. The results showed that G-Rbl (1 mg/100g B.W) and G-Rc (1 ma/100g B.W) caused marked increases of LDH A-mRNA contents by respectively 1.9- and 1.5-fold in rat liver at 5·hours after partial hepatectomy. Dose dependent effect of G-Rbl and G-Rc (1-25 mg/100g B.W) on the LDH A-mRNA levels on regenerating rat liver were also analyzed. The maximal in- creases of liver LDH A-mRNA levels were observed with the doses of 1 mg for G-Rbl and 5 mg for G-Rc However, when the administration doses of G-Kbl and G-Rc were increased to 20 mg, G-Rbl caused a marked decrease of LDH A-mRNA level to 61% of those in sham-operated rat liver In contrast, G-Rc slightly decreased the liver LDH A-mRNA contents by 30% as compared to those of the maximum value but still maintained 22% higher LDH A-mRNA levels then those of sham-operated rate liver. On the basis of these experimental results, we conclude that ginseng saponin, G-Rb 1 and G·Rc have stimulatory effect at the lower concentration (1 mg/100g B.W) and inhibitory effect at the higher concentration (20 moi loos 5.W) on the LDH A-gene transcription during regeneration of rat liver, Additionally we also investigated the stimulatory effects of ginsenosides on the protein and DNA synthetic activities in hepatocyte primary cell cultures isolated from regenerating rat liver. Both of G·Rc and -Re increased the synthetic rates of hepatocytes proteins and DNA at the administration doses of 50 ug and 100 ug/3 ml/dish respectively representing 1.3-1.6 fold increases. From these results we postulate that G-Rc and -Re may have a mitogen enhancer activity for the hepatocyte proliferation during rat liver regeneration period. Keywords Inductive effects of ginsenosides, G-Rb, -Rc, and -Re, rat LDH A-gene transcription, the sin thetic rate of proteins and DNA in regeneration rat liver.

• BMB Reports
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• v.43 no.5
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• pp.344-348
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• 2010

Messenger ribonucleoprotein particles (mRNPs) are used to transport mRNAs along neuronal dendrites to their site of translation. Staufen2 is an mRNA-binding protein expressed in the cell bodies and cellular processes of different brain cells. It is notably involved in the transport of dendritic mRNAs along microtubules. Its knockdown expression was shown to change spine morphology and impair synaptic functions. However, the identity of Staufen2-bound mRNAs in brain cells is still completely unknown. As a mean to identify these mRNAs, we immunoprecipitated Staufen2-containing mRNPs from embryonic rat brains and used a genome wide approach to identify Staufen2-associated mRNAs. The genome wide approach identified 1780 mRNAs in Staufen2-containing mRNPs that code for proteins involved in cellular processes such as post-translational protein modifications, RNA metabolism, intracellular transport and translation. These results represent an additional and important step in the characterization of Staufen2- mediated neuronal functions in rat brains.

• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.275-282
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• 1993

Liver microsomal epoxide hydrolase (mEH) is active in the detoxification of epoxide-containing reactive intermediate. Previous studies in this laboratory have shown that thiazole and pyrazine are efficacious inducers of mEH in rats with large increases in mEH mRNA levels (Carcinogensis, Kim et al, 1993). mEH was purified to electrophoretic homogeneity from thiazole-induced rat hepatic microsomes using DEAE-cellulose column chromatography whereas another protein $({\sim}43\;kDa)$ was co-purified with mEH from pyrazine-induced rat hepatic micrsomes (200 mg/kg body weight/day, ip, 3d). The antibody raised from a rabbit against mEH protein purified from thiazole-induced rat hepatic microsomes appeared to specifically recognize mEH protein in rat hepatic microsomes, as assessed by immunoblotting analysis. Immunoblotting analyses revealed a 10- and 7-fold increase in mEH levels in the hepatic microsomes isolated from thiazole- and pyrazine-treated rats, respectively. Moreover, immunoblotting analysis showed cross-reactivity of the mEH antibody with a 43 kDa protein in pyrazine-induced rat hepatic microsomes and with co-purified 43 kDa protein in purified fractions. The ratio between the 43 kDa protein and mEH in pyrazine-induced rat microsomes or in purified fractions was ${\sim}1$ to 15. N-terminal amino acid sequence analysis of both purified rat mEH and 43 kDa protein revealed that 10 out of 12 amino acids in N-terminus of the 43 kDa protein were identical with the mEH sequence with two amino acid residues of the 43 kDa protein undetermined. Either thiazole or pyrazine treatment, however, failed to increase the levels of mEH protein in rabbits while pyrazine caused elevation of the 43 kDa protein in this species, as determined by irnrnunoblotting analysis. These results demonstrated that treatment of rats with either thiazole or pyrazine causes elevation in hepatic mEH expiession whereas pyrazine treatment results in induction of another mEH-related 43 kDa protein and that a distinct species difference exists between rats and rabbits in the induction of mEH by these xenobiotics.

• Korean Journal of Animal Reproduction
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• v.14 no.1
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• pp.31-35
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• 1990

The viability and developmental potential of rat oocyte was assessed by the use of eosin B. Dye was prepared as a stock solution to contain 1.0 mg eosin B per ml of Brinster's Medium for Ovum Culture plus glucose (BMOC) -2 medium. Three dye concentrations were selected for the Oocytes from rat ovarian follicles were collected and assessed under various conditions of heat oocyte studies by dilution of the stock solution with BMOC: 0.12mM, 0.60mM and 1.20mM. treatment and preservation duration by dye exc¬lusion assay using eosin B. It is suggested that live oocyte excludes eosin B whereas dead oocyte does not.

• Journal of Environmental Science International
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• v.12 no.10
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• pp.1131-1136
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• 2003

To examine whether salt stress would alter or not contractility of isolated rat aorta, under anesthesia with sodium pentobarbital(50 mg kg-1 i.p.), male Sprague Dawley rats(300-330 g) were subjected to 0, 50, and 150 mM of sodium chloride at 37$^{\circ}C$ for 60 min. where as the sham group was left at modified Krebs-bicarbonate solution. To measure contractile response of vascular ring preparation isolated from rat was determined in organ bath and was recorded on physiograph connected to isometric transducer. And the strip was checked for expression of heat shock protein(Hsp) by Western blotting. One, three and eight hours later, we measured vascular contractility of isolated rat aorta treated with KCI, phenylephrine from organ bath study. The dose-vascular responses of potassium chloride and phenylephrine showed a little augmentation by NaCl concentration in the strips exposed to NaCl for 8 hours. And the response of relaxation induced by nitroprusside and acetylcholine was not influenced by NaCl stress in isolated aorta ring for 8 hours, respectively. Expression pattern of Hsp 70 of vascular muscle in isolated rat aorta showed a little increase in 150 mM NaCl group at 8 hours after NaCl treatment but not at 3 hours, and Hsp 60 expression of rat aorta was markedly increased in 50 mM NaCl group at 8 hours after NaCl treatment. Taken together, NaCl induced dose-and time dependent accumulation of the Hsp but not affected contraction of rat aorta. These data suggest that short term high salt stress was not sufficient to induce hypertension of rat aorta.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.255.2-255.2
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• 2002

The present study was designed to investigate the effects of green tea extract (GTE) and epigallocatechin gallate (EGCG) on secretion of catecholamines (CA) in the isolated perfused rat adrenal gland. In the presence of GTE (100 ${\mu}$g/$m\ell$) into an adrenal vein for 60 min. CA secretory responses evoked by ACh (5.32 mM), high K＋ (56 mM) and Bay-K-8644 (10 ${\mu}$M for 4 min) from the isolated perfused rat adrenal glands were greatly inhibited in a time-dependent fashion. (omitted)