• Korean journal of applied entomology
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• v.43 no.2
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• pp.155-162
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• 2004

Serotonin receptor binds to serotonin (5-HT) and activates effector proteins such as adenylyl cyclase, phospholipase C, cyclic GMP phosphodiesterase or ion channel through G protein on the cell membrane, resulting in various physiological responses like diuresis, memory and development. To examine the comparative expression of the 5-HT$\_$7/ receptor of Aedes aegypti, the Aedes 5-HT$\_$7/ receptor gene was transfected into Drosophila Schneider2 (S2) cells and mammalian Chinese hamster ovary (CHO)-Kl cells. The expression of the Aedes 5-HT$\_$7/ receptor gene in selected cell lines, Tr-CHO and Tr-S2, was confirmed with reverse transcription-PCR, Western blot and immunocytochemistry. Compared with the induced intracellular cAMP level of Tr-S2 cell line to 5-HT, the induced cAMP in the Tr-CHO cell line was over 9 times higher and was dose-dependent. These results suggest that the functionality of Aedes 5-HT$\_$7/ receptor is much more effective in mammalian CHO-K 1 cells and that the Tr-CHO cell line expressing Aedes 5-HT$\_$7/ receptor can be used for synthetic agonist or antagonist candidate screening.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.475-481
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• 1999

Yeast extracts were prepared using either autolysis or enzymatic digestion methods for industrial application of the Saccharomyces cerevisiae B24 strain developed previously to have high RNA content. Extraction ratio of yeast extract from yeast cell reached 65% when autolysis of yeast slurry having 10% solid content was induced at $50^{\circ}C$ and pH 5.0 by agitating with 100 rpm. However, neither 5'-IMP nor 5'-GMP was detected from the autolyzate. In another attempt to prepare a yeast extract S. cerevisiae B24 culture was treated at $90^{\circ}C$ and then treated by various enzymes including ${\beta}-1,3-glucanase$, phosphodiesterase (nuclease P1), adenylic deaminase, and a protease. The yeast extract prepared by the enzymatic digestion method contained 3.2g of 5'-IMP and 5'-GMP/100g dry yeast extract.

• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.276-280
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• 1993

Cell lytic enzyme, 5'-phosphodiesterase, and AMP-deaminase were used to produce yeast extract as a natural seasoning from beer yeast cells. Prior to the addition of cell lytic enzyme, heat treatment was performed to increase the cell wall degradation` the optimum condition of the cell lytic enzyme was 50C at pH 7.0. The production yields by the enzymatic method and conventional autolysis method were 42% and 35%, respectively. The total quantity of 5'-nucleotides, GMP and IMP, produced by enzymatic method was increased by 45% than that by the conventional method. Futhermore, the operation time of enzymatic method was only 6.5 hrs, significantly reduced from 24 hrs of the conventional method.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.249.1-249.1
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• 2002

This study was carried out to demonstrate the effects of oral administration of DA-8159. a selective phosphodiesterase 5 inhibitor. on development of pulmonary hypertension induced by monocrotaline (MCT). MCT-treated rats(60mg/kg) were divided into three groups and orally administered vehicle, 1 mg/kg or 5 mg/kgg of DA-8159 twice a day for 3 weeks. Increased right ventricular weights, medial wall thickening in pulmonary arteries. myocardial fibrosis, decrease of plasma cyclic guanosine monophosphate (cGMP) level and body weight gains were shown in MCT group. (omitted)

• Journal of Embryo Transfer
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• v.27 no.3
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• pp.163-169
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• 2012

The 3-isobutyl-1-methylxanthine (IBMX) is non-selective phosphodiesterase and is able to prevent resumption of meiosis by maintaining elevated cyclic AMP (cAMP) concentrations in the oocyte. The present study was conducted to analyze: (1) nuclear maturation (examined by the Hoechst staining), (2) whether cytoplasmic maturation (examined by the intracellular glutathione (GSH) concentration) of porcine oocytes is improved during meiotic arrest after prematuration (22 h) with IBMX. Before in vitro maturation (IVM), oocytes were treated with 1 mM IBMX for 22 h. After 22 h of pre-maturation, the higher rate of IBMX treated group oocytes were arrested at the germinal vesicle (GV) stage (42.3%) than control IVM oocytes (10.1%). It appears that the effect of IBMX on the resumption of meiosis has shown clearly. In the end of IVM, the reversibility of the IBMX effect on the nuclear maturation has been corroborated in this study by the high proportions of MII stage oocytes (72.5%) reached after 44 h of IVM following the 22 h of inhibition. However, intracellular GSH concentrations were lower in the oocytes treated with IBMX than the control oocytes (6.78 and 12.94 pmol/oocyte, respectively). These results demonstrate that cytoplasmic maturation in porcine oocytes pre-treated with IBMX for 22 h did not equal that of control oocytes in the current IVM system. These results indicate that pre-maturation with IBMX for 22 h may not be beneficial in porcine IVM system.

• The Korean Journal of Pain
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• v.20 no.1
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• pp.21-25
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• 2007

Background: Intrathecal sildenafil has produced antinociception by increasing the cGMP through inhibition of phosphodiesterase 5. Spinal opioid receptor has been reported to be involved in the modulation of nociceptive transmission. The aim of this study was to examine the role of opioid receptor in the effect of sildenafil on the nociception evoked by formalin injection. Methods: Rats were implanted with lumbar intrathecal catheters. Formalin testing was used as a nociceptive model. Formalin-induced nociceptive behavior (flinching response) was observed. To clarify the role of the opioid receptor for the analgesic action of sildenafil, naloxone was administered intrathecally 10 min before sildenafil delivery, and formalin was then injected 10 min later. Results: Intrathecal sildenafil produced dose-dependent suppression of flinches in both phases during the formalin test. Intrathecal naloxone reversed the analgesic effect of sildenafil in both phases. Conclusions: Sildenafil is active against the nociceptive state that's evoked by a formalin stimulus, and the opioid receptor is involved in the analgesic action of sildenafil at thespinal level.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.1
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• pp.43-50
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• 2004

Ischemia followed by reperfusion in the presence of polymorphonuclear leukocytes (PMNs) results in a marked cardiac contractile dysfunction. Amrinone, a specific inhibitor of phosphodiesterase 3, has an antioxidant activity against PMNs. Therefore, we hypothesized that amrinone could attenuate PMNs-Induced cardiac dysfunction by suppression of reactive oxygen species (ROS) produced fby PMNs. In the present study, we examined the effects of amrinone on isolated ischemic (20 min) and reperfused (45 min) rat hearts perfused with PMNs. Amrinone at $25\;{\mu}M$, given to hearts during the first 5 min of reperfusion, significantly improved coronary flow, left ventricular developed pressure (P<0.001), and the maximal rate of development of left ventricular developed pressure (P<0.001), compared with ischemic/reperfused hearts perfused with PMNs in the absence of amrinone. In addition, amrinone significantly reduced myeloperoxidase activity by 50.8%, indicating decreased PMNs infiltration (p< 0.001). Superoxide radical and hydrogen peroxide production were also significantly reduced in fMLP- and PMA-stimulated PMNs pretreated with amrinone. Hydroxyl radical was scavenged by amrinone. fMLP-induced elevation of $[Ca^{2+}]_i$ was also inhibited by amrinone. These results provide evidence that amrinone can significantly attenuate PMN-induced cardiac contractile dysfunction in the ischemic/reperfused rat heart via attenuation of PMNs infiltration into the myocardium and suppression of ROS release by PMNs.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.128-128
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• 2001

Toxic effects of a new phosphodiesterse-5 inhibitor, DA-8159, were investigated in Sprague-Dawley rats by repeated oral administration. Four groups of 10 male and 10 female rats were treated with DA-8159 at a dose of 0, 40, 80, or 320 mg/kg/day for 4 weeks.(omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.127-127
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• 2001

Single-dose toxicity of a new phosphodiesterse inhibitor-5, DA -8159, was studied in rats via oral and intravenous routes and in mice via oral route. In addition, genotoxic potential of DA-8159 was investigated by using of the battery of test; reverse mutation test on bacteria, chromosomal aberration test on cultured mammalian cells and micronucleous test on mice.(omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.250.2-251
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• 2002

DA-8159 is a new. highly selective. potent cyclic-GMP phosphodiesterase 5 inhibitor developed by Dong-A Pharmaceutical Company(Kyunggi, Korea) as an oral drug for the treatment of erectile dysfunction. NO- cGMP signal transduction pathway plays a key role for relaxation of corpus cavernosal smooth muscle. In this study. the efficacy of DA-8159 was evaluated by measuring the length of uncovered penile mucosa in spinal cord injury(SCI) rabbits. (omitted)