• Korean Journal of Veterinary Research
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• v.27 no.2
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• pp.201-206
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• 1987

This study was carried out to investigate the action of ATP, which has been known as the neurotransmitter of noncholinergic- and nonadrenergic-nerve, on the motility of immature pig uterine smooth muscle. The results were summarized as follows; 1. The contraction and the contractile responses caused by ATP were increased in a dose-dependent manner between the concentration of ATP $10^{-6}M$ and $10^{-3}M$. The maximal contractile effect was appeared at the concentration of ATP $10^{-3}M$ and it was 70.2% of 100mM K contraction. 2. The contractile responses induced by ATP ($10^{-4}M$) were not blocked by the pretreatment with cholinergic receptor blocker, atropine ($10^{-6}M$). 3. The contractile responses induced by ATP ($10^{-4}M$) were not blocked by pretreatment with ${\alpha}$-adrenergic receptor blocker, phentolamine ($10^{-6}M$) and ${\beta}$-adrenergic receptor blocker, propranolol ($10^{-6}M$). 4. The contractile response induced by ATP ($10^{-4}M$) was not blocked by the pretreatment with $H_1-receptor$ blocker, pyrilamine ($10^{-6}M$) and $H_2-receptor$ blocker, cimetidine ($10^{-6}M$).

• Korean Journal of Animal Reproduction
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• v.20 no.4
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• pp.395-412
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• 1997

Mammalian eggs are ovulated arrested at meiotic metaphase II until fertilization. Generally in mammals, fertilization results in a series of intracellular calcium oscillations that are mediated by inositol triphosphate (IP$^3$) or cyclic adenosine diphosphoribose (cADPr). The high levels of maturation promotion factor (MPF) within the cell decrease, pronuclei form, the cytoskeleton is reorganized and proteins are post-translationally modified. If all is normal, the newly formed embryo initiates the developmental program specific to that species. Artificial methods of producing these effects in pig oocytes are discussed. One potential mechanism mediated via a signal transduction pathway is present in pig oocytes. Stimulation of this pathway leads to the early events following fertilization, and electrical stimulation leads to apparently normal de v velopment to day 12. Further studies are needed to determine which mechanism(s) the sperm uses to initiate development.

• Journal of the Korean Electrochemical Society
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• v.15 no.4
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• pp.249-255
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• 2012

The planar-type amperometric creatinine biosensor employing an additional enzyme layer containing creatine kinase and adenosine triphosphate was developed to eliminate severe interference from creatine. In the additional enzyme layer, an interfering substance, creatine is converted to noninterfering product, phosphocreatine. Furthermore, the carbon electrode electroplated with Pt black(Pt-B) was employed to fabricate creatinine biosensors with improved sensor performance(e.g., sensitivity, reliability, and reproducibility). The creatinine levels in an unknown sample were determined within less than 5% errors using creatinine microsensors equipped in a flow-cell cartridge.

• Biomedical Science Letters
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• v.20 no.2
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• pp.70-76
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• 2014

In this study, we investigated the effect of DMSO, a highly dipolar organic liquid, in collagen ($5{\mu}g/ml$)-stimulated platelet aggregation. DMSO inhibited platelet aggregation at 0.5% by inhibiting production of thromboxane $A_2$ ($TXA_2$) which was associated with blocking cyclooxygenase (COX)-1 activity and $TXA_2$ synthase. In addition, DMSO significantly increased the formation of cyclic adenosine monophosphate (cAMP) from adenosine triphosphate (ATP) and cyclic guanosine monophosphate (cGMP) from guanosine triphosphate (GTP). On the other hand, DMSO (0.1~0.5% concentration) did not affect the LDH release which indicates the cytotoxicity. Based on these results, DMSO has anti-platelet effect by regulation of several platelet signaling pathways, therefore we suggest that DMSO could be a novel strategy on many thrombotic disorders.

• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.425-431
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• 2019

Platelet activation is essential for hemostatic process on blood vessel damage. However, excessive platelet activation can cause some cardiovascular diseases including atherosclerosis, thrombosis, and myocardial infarction. Scoparone is commonly encountered in the roots of genus Artemisia or Scopolia, and has been studied for its potential pharmacological properties including immunosuppression and vasorelaxation, but antiplatelet effects of scoparone have not been reported yet. We investigated the effect of scoparone on human platelet activation prompted by an analogue of thromboxane A₂, U46619. As the results, scoparone dose-dependently increased cyclic adenosine monophosphate (cAMP) levels as well as cyclic guanosine monophosphate (cGMP) levels, both being aggregation-inhibiting molecules. In addition, scoparone strongly phosphorylated inositol 1, 4, 5-triphosphate receptor (IP3R) and vasodilator-stimulated phosphoprotein (VASP), substrates of cAMP dependent kinase and cGMP dependent kinase. Phosphorylation of IP₃R by scoparone resulted in inhibition of Ca²⁺ mobilization in calcium channels in a dense tubular system, and phosphorylation of VASP by scoparone led to an inability of fibrinogen being able to bind to αIIb/β3. Finally, scoparone inhibited thrombin-induced fibrin clotting, thereby reducing thrombus formation. Therefore, we suggest that scoparone has a strong antiplatelet effect and is highly probable to prevent platelet-derived vascular disease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.59-73
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• 1980

A detailed procedure was described for the isolation of cratine kinase (ATP-Creatine phosphotransferase, E. C. 2. 7. 3. 2.) from the muscle of the snake Bungarus fasciatus. The original isolation procedure of Kuby et al. for the rabbit muscle enzyme has been modified and extended to include a chromatographic step. The properties of the enzyme have been investigated and kinetic constants for the reverse reactions determined as the followings: 1) A molecular weight of the enzyme was determined by gel filteration on Sephadex G-100 and by electrophoresis on SDS-polyacrylamide was 86,000. 2) Two reactive sulphydryl groups were detected with dithiobis nitrobenzoic acid (DTNB). 3) The nucleotide substrate specificity in the reverse reaction was determined as ADP*2'-dADP＞GDP＞XDP＞UDP with magnesium as the activating metal ion. 4) The order of the metal specificity in the reverse reaction Mg>Mn>$Ca{\sim}Co$ was determined with ADP as substrate. 5) A detailed kinetic analysis was carried out in the reverse direction with $MaADP^-$ as the nucleotide substrate. Initial velocity and product inhibition studies($MaADP^{2-}$ competitive with respect to MgADP- and noncompetitive with respect to $N-phosphorycreatine^{2-}$ ; Creatine competitive with respect to $N-phosphorycreatine^{2-}$ and noncompetitive with respect to Ma $ADP^-)$ indicated that the reaction obeyed a sequential mechanism of the rapid equilibrium random type.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2034-2042
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• 2015

A one-pot process of enzymatic synthesis of deoxythymidine-5'-triphosphate (5'-dTTP) employing whole cells of recombinant Escherichia coli coexpressing thymidylate kinase (TMKase) and acetate kinase (ACKase) was developed. Genes tmk and ack from E. coli were cloned and inserted into pET28a(+), and then transduced into E. coli BL21 (DE3) to form recombinant strain pTA in which TMKase and ACKase were simultaneously overexpressed. It was found that the relative residual specific activities of TMKase and ACKase, in pTA pretreated with 20 mM ethylene diamine tetraacetic acid (EDTA) at 25℃ for 30 min, were 94% and 96%, respectively. The yield of 5'-dTTP reached above 94% from 5 mM deoxythymidine 5'-monophosphate (5'-dTMP) and 15 mM acetyl phosphate catalyzed with intact cells of pTA pretreated with EDTA. The process was so effective that only 0.125 mM adenosine-5'-triphosphate was sufficient to deliver the phosphate group from acetyl phosphate to dTMP and dTDP.

• The Korean Journal of Nuclear Medicine
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• v.32 no.3
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• pp.250-258
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• 1998

Purpose: ATP (adenosine triphosphate) is a potent coronary vasodilator with a rapid onset of action and a very short half-life. Myocardial perfusion scintigraphy with intravenous ATP has not yet been sufficiently proven in the diagnosis, follow-up, and risk stratification of coronary artery disease. The purpose of this study was to evaluate the safety, feasibility and diagnostic accuracy of pharmacologic stress thallium-201 myocardial SPECT using an intra-venous ATP infusion in patients with suspected coronary artery disease. Materials and Methods: Thallium-201 myocardial SPECT in 319 patients with suspected coronary artery disease were performed after the infusion of ATP (0.08 mg/kg/min for 6 min). The adverse effects were carefully monitored. Coronary angiography was also performed within 3 weeks. Results: Although 76.5% of the patients had some adverse effects, they were transient, mild, and well tolerated. In all patients, the ATP infusion protocol was completed and only 2 patients required aminophylline. The adverse effects were dyspnea in 63%, headache in 31%, flushing in 21%, chest pain in 14% and abdominal discomfort in 5% of the patients. The sensitivity and specificity were 80% and 90% respectively. Conclusion: Thallium-201 myocardial SPECT after 6 min-infusion of ATP at a rate of 0.08 mg/kg/min is safe and has a diagnostic value in detecting coronary artery disease.

• Biomolecules & Therapeutics
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• v.8 no.4
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• pp.338-348
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• 2000

The present study was attempted to determine the effect of 5'-(N'-ethylcarboxamido) adenosine (NECA), which is an potent $A_2$-adenosine receptor agonist, on catecholamine (CA) secretion evoked by cholinergic stimulation, membrane depolarization and calcium mobilization from the isolated perfused rat adrenal gland. NECA (20 nM) perfused into the adrenal vein for 60 min produced a time-related inhibition in CA secretion evoked by ACh (5.32x10$^{-3}$ M), high $K^{+}$(5.6x10$^{-2}$ M), DMPP (10$^{-4}$ M for 2 min), McN-A-343 (10$^{-4}$ M for 2 min), cyclopiazonic acid (10$^{-5}$ M for 4 min) and Bay-K-8644 (10$^{-5}$ M for 4 min). Also, in the presence of $\beta$,${\gamma}$-methylene adenosine-5'-triphosphate (MATP), which is also known to be a selective $P_{2x}$-purinergic receptor agonist, showed a similar inhibition elf CA release evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid. However, in adrenal glands preloaded with 20$\mu$M NECA for 20 min under the presence of 20$\mu$M 3-isobutyl-1-methyl-xanthine (IBMX), an adenosine receptors antagonist, CA secretory responses evoked by ACh, high potassium, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were much recovered in comparison to the case of NECA-treatment only. Taken together, these results indicate that NECA causes the marked inhibition of CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as by membrane depolarization. This inhibitory effect may be mediated by inhibiting influx of extracellular calcium and release in intracellular calcium in the rat adrenomedullary chromaffin cells through the adenosine receptor stimulation. Therefore, it is suggested that the inhibitory mechanism of adenosine receptor stimulation may play a modulatory role in regulating CA secretion.n.n.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.343-347
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• 1994

The effects of low and high-voltage-electrical-stimulation and storing temperature on concentration of adenosine triphosphate (ATP) related compounds were studied in M. Semitendinosus muscles from Korean native cattle. Seven beef carcasses were split, the one side was electrically stimulated for 1 minute by using stimulator adjusted to 400 V/60 Hz as high voltage or to 110 V/60 Hz as low voltage while the other side served as an unstimulated control. Both side samples were incubated at $5^{\circ}C\;and\;15^{\circ}C$ for 3 days. During storage, the concentration of ATP and its breakdown products were measured as a function of time. Significant differences (p<0.05) were observed in the variance of ATP, adenosine diphosphate (ADP) and inosine monophosphate (IMP) levels between low-or high-voltage-electrically stimulated muscles and unstimulated control at just after post-stimulation. The decomposition of adenosine compounds and the production of inosine compounds of low-voltage-electrically stimulated muscles were advanced more slowly than those of high-voltage-treatment muscles. With increasing storage time, the influence of electrical stimulation on changes of ATP related compounds in meat was decreased, but storing temperature begin to affect their concentration. Significant difference in the Hypoxanthine levels (p<0.05) was found of sample stored for 48 hours at $15^{\circ}C$ from samples stored at $5^{\circ}C$ regardless of electrical stimulation treatemt. IMP and inosine values in electrically stimulated muscles, higher than of a control during 72 hours of storage, indicated rapid production of flavor compounds in beef.