• Biomolecules & Therapeutics
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• v.7 no.2
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• pp.105-111
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• 1999

Nitric oxide (NO), a cellular messenger synthesized from L-arginine by NO synthase (NOS, EC.1.14.13.39), is considered to be a regulator of gastric secretion. In the present study, the role of NO in the regulation of exocrine secretion was investigated in rat gastric chief cells. Treatment of chief cells with carba-chol resulted in an increase in the arginine conversion to citrulline, the amount of $NO_{x}$, the release of pepsine-gen, and the level of cGMP Especially, carbachol-stimulated increase of arginine to citrulline transformation, the amount of $NO_{x}$, cGMP level and the release of pepsinogen were partially reduced by the natural NOS inhibitor, $N^{G}$-monomethyl-L-arginine (MMA) and $N^{G}$, $N^{G}$-dimethyl-L-arginine (DMA). Furthermore, MMA- and DMA-induced decrease of pepsinogen secretion showed dose-dependent patters. Activation of NOS is one of the early events in receptor-mediated cascade of reactions in gastric chief cells and NO, not completely, but partially mediates gastric secretion. Agonist-stimulated pepsinogen secretion in chief cells has been considered to be mediated in adenosine 3',5'-cyclic monophosphate pathway and/or guanosine 3', 5'-cyclic monophosphate (cGMP) pathway. Taken together, the above results suggest that partial decrease of exocrine secretion following treatment of NOS inhibitor may result from the inactivation of NOS and subsequent guano- late cyclase, and NO/cGMP pathway may play a pivotal role in exocrine secretion.

• Biomolecules & Therapeutics
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• v.19 no.2
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• pp.218-223
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• 2011

In this study, we investigated the effect of spinach saponin-enriched fraction (SSEF) on collagen (10 ${\mu}g/ml$)-stimulated platelet aggregation. SSEF inhibited collagen-induced platelet aggregation, and which was involved in the inhibition of thromboxane $A_2$ ($TXA_2$) production, an intracellular $Ca^{2+}$-agonist as an aggregation-inducing autacoidal molecule. In addition, SSEF significantly increased the formation of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), intracellular $Ca^{2+}$-antagonists as aggregation-inhibiting molecules, in collagen-stimulated platelets. These results suggest that SSEF might inhibit $Ca^{2+}$-elevation and $TXA_2$ formation by increasing the production of $Ca^{2+}$-antagonistic molecules cAMP and cGMP. These mean that SSEF is a potent inhibitor of collagen-stimulated platelet aggregation. On the other hand, prothrombin time (PT) and activated partial thromboplastin time (APTT) were potently prolonged by SSEF. These findings suggest that SSEF prolongs the internal time between the conversion of fibrinogen to fibrin. Accordingly, our data demonstrate that SSEF may be a crucial tool for a negative regulator during platelet activation and blood coagulation on thrombotic diseases.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1570-1574
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• 2004

A flock of AA breed chickens were reared in peterstme brood-vait chamber and were provided with high energy pelleted feed. At 14 d of age, a total of 350 birds were randomly divided into 3 groups as follows: 100 birds were exposed to normal ambient temperature of 20$^{\circ}C$ for control group; 150 birds were exposed to lower ambient temperature of 11$^{\circ}C$ to induce ascites (treatment I); and another group of 100 birds were exposed to lower ambient temperature of 11$^{\circ}C$ and fed diet containing 1% L-arginine for ascitic prophylactic treatment (treatment II). Samples were collected from blood and abdominal fluid of chicken at 3, 4, 5, 6 and 7 wk of age subsequently, to analysis the contents of plasma endothelin (ET-1), angiotensin II (Ang II), cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP). The results indicated that the contents of cAMP, cGMP, and Ang II in reatment I and ascitic broilers were higher than the corresponding control group (p<0.01, p<0.05), ET-1 of preascitic broilers were control group (p<0.05), while there was an insignificant difference with later ascitic broilers. The contents of cAMP and cGMP in treatment II were higher than the treatment I and control groups (p<0.01, p<0.05), whereas, the contents of Ang II were gradually decreased compared to the control group (p<0.05), the contents of ET-1 were insignificantly different. On further analysis, the increased plasma Ang II at low ambient temperature condition in broilers made endothelium cell secretion of increased ET-1, cAMP, cGMP and decreased NO. Therefore, low temperature accelerated ascites syndrome in broilers. Supplemently L-arginine can decrease ET-1, and increase cAMP and cGMP. It is concluded that cAMP mediated in broilers pulmonary hypertension syndrome.

• Korean Journal of Veterinary Research
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• v.56 no.2
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• pp.67-74
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• 2016

Tomato extract has been shown to exert antiplatelet activity in vitro and to change platelet function ex vivo, but with limitations. In this study, antiplatelet activity of water soluble tomato concentrate (Fruitflow I) and dry water soluble tomato concentrate (Fruitflow II) was investigated using rat platelets. Aggregation was induced by collagen and adenosine diphosphate and granule-secretion, $[Ca^{2+}]_i$, thromboxane B2, cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) levels were examined. The activation of integrin ${\alpha}_{IIb}{\beta}_3$ and phosphorylation of signaling molecules, including mitogen-activated protein kinase (MAPK) and PI3K/Akt, were investigated by flow cytometry and immunoblotting, respectively. Prothrombin time (PT) and activated partial thromboplastin time (aPTT) were examined. Moreover, in vivo thrombus weight was tested by an arteriovenous shunt model. Fruitflow I and Fruitflow II significantly inhibited agonist induced platelet aggregation, adenosine triphosphate and serotonin release, $[Ca^{2+}]_i$, and thromboxane B2 concentration, while having no effect on cAMP and cGMP levels. Integrin ${\alpha}_{IIb}{\beta}_3$ activation was also significantly decreased. Moreover, both concentrates reduced phosphorylation of MAPK pathway factors such as ERK, JNK, P38, and PI3K/Akt. In vivo thrombus formation was also inhibited. Taken together, these concentrates have the potential for ethnomedicinal applications to prevent cardiovascular ailments and can be used as functional foods.

• Food Science of Animal Resources
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• v.33 no.4
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• pp.508-514
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• 2013

Taste-active compounds (e.g., amino acids and nucleotides) play an important role in contribution to the gustatoty sensation of food. The current study aimed to examine the differences in taste-active compounds between different beef muscles, breeds and aging periods. We have chosen the longissimus dorsi and semitendinosus muscles of Hanwoo breed and longissimus dorsi muscle of Angus breed for the investigation of the aforementioned compounds. Hanwoo muscles were aged for 7 or 28 d, and Angus samples were aged for 28 d at $4^{\circ}C$. Results revealed that 8 out of the 18 detected free amino acids (FAA) showed significant (p<0.05) differences between the two Hanwoo muscles. Twelve FAAs showed aging effect (p<0.05) in which the amounts of 8 FAAs significantly increased as aging time increased. Inosine 5-monophosphate (IMP), hypoxanthine (Hx) and inosine showed significant (p<0.05) differences between the Hanwoo muscles, aging resulted in an increase in amounts of these nucleotides. Hanwoo beef had significantly (p<0.05) higher total amount of sweet amino acids than the Angus ones in that 15 amino acids showed differences (p<0.05) between the two breeds. Amounts of guanosine 5-monophosphate (GMP) and Hx were significantly higher (p<0.05) for Angus beef. Current study indicated that muscle type, breed and aging period had large variations in free amino acid and nucleotide contents, which may subsequently affect the taste attributes of cooked beef.

• Animal Bioscience
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• v.35 no.7
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• pp.1080-1090
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• 2022

Objective: This study aimed to characterize the effect of pre-treated black garlic (BG) extracts addition into retorted Korean ginseng chicken soup (Samgyetang) on the fatty acid composition and flavour-related indexes. Methods: Four different treatments; Samgyetang made with a 5% (w/w) addition of garlic (G), fresh BG (FBG), oven-dried BG (DBG), or encapsulated BG (EBG) extracts were developed and compared to negative control (NC) without any extract addition. Prepared samples were cooked via retorting at 121.1℃, 1.5 kgf/cm² for 1 h. Results: The BG treated samples were higher in C18:3n3 and C18:2n6 fatty acids, with thrombogenic index was 18% to 20% lower than the NC. EBG yielded the highest umami-related nucleotides (5'-guanosine monophosphate and 5'-inosine monophosphate) and modified some free amino acid (alyne, phenylalanine and leucine) thus possessed the highest equivalent umami concentration among samples. Some individual aldehydes (pentanal, hexanal, and heptanal) were lower, while furans and volatile sulfur compounds were higher than the NC and G treatment group, indicating a potential suppression of unpleasant flavour alongwith the intensificiation of favourable flavour from the addition of BG extracts into retorted Samgyetang. Conclusion: Taken together, the synergistic results of this study indicate that incorportating suitable pre-treatment of BG extract could be of critical importance for the development of the retorted Samgyetang with improved flavour and functionalities.

• Journal of Ginseng Research
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• v.47 no.5
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• pp.638-644
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• 2023

Background: The anti-platelet activity of the saponin fraction of Korean Red Ginseng has been widely studied. The saponin fraction consists of the panaxadiol fraction (PDF) and panaxatriol fraction (PTF); however, their anti-platelet activity is yet to be compared. Our study aimed to investigate the potency of anti-platelet activity of PDF and PTF and to elucidate how well they retain their anti-platelet activity via different administration routes. Methods: For ex vivo studies, Sprague-Dawley rats were orally administered 250 mg/kg PDF and PTF for 7 consecutive days before blood collection via cardiac puncture. Platelet aggregation was conducted after isolation of the washed platelets. For in vitro studies, washed platelets were obtained from Sprague-Dawley rats. Collagen and adenosine diphosphate (ADP) were used to induce platelet aggregation. Collagen was used as an agonist for assaying adenosine triphosphate release, thromboxane B2, serotonin, cyclic adenosine monophosphate, and cyclic guanosine monophosphate (cGMP) release. Results: When treated ex vivo, PDF not only inhibited ADP and collagen-induced platelet aggregation, but also upregulated cGMP levels and reduced platelet adhesion to fibronectin. Furthermore, it also inhibited Akt phosphorylation induced by collagen treatment. Panaxadiol fraction did not exert any antiplatelet activity in vitro, whereas PTF exhibited potent anti-platelet activity, inhibiting ADP, collagen, and thrombin-induced platelet aggregation, but significantly elevated levels of cGMP. Conclusion: Our study showed that in vitro and ex vivo PDF and PTF treatments exhibited different potency levels, indicating possible metabolic conversions of ginsenosides, which altered the content of ginsenosides capable of preventing platelet aggregation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.5
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• pp.1271-1277
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• 2007

This study was designed to investigate the effects of Sagunja-tang Extract & Zingiberis rhizoma recens Juice (SEZJ) and Zingiberis rhizoma recens Juice (ZRJ) on the changes in regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats. The results were as follows ; SEZJ and ZRJ significantly increased rCBF in a dose-dependent manner, while it did not change MABP. This results suggest that SEZJ and ZRJ significantly increased rCBF by dilating pial arterial diameter. Increase of SEZJ-induced rCBF was significantly inhibited by pretreatment with methylene blue (10 ${\mu}g/kg$, i.p.), an inhibitor of guanylate cyclase, and indomethacin (1 mg/kg, i.p.), an inhibitor of cyclooxygenase. SEZJ-induced MABP was significantly increased by pretreatment with indomethacin but was not changed by methylene blue. These results suggested that the action of SEZJ was mediated by cyclic 3',5'-guanosine monophosphate.

• Development and Reproduction
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• v.20 no.4
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• pp.359-365
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• 2016

Intact germinal vesicle (GV) arrest and release are essential for maintaining the fertility of mammals inducing human. Intact germinal vesicle release, maturation of oocytes is maintained by very complex procedures along with folliculogenesis and is a critical step for embryonic development. Cyclic guanosine monophosphate (cGMP) has been suggested a key factor for meiotic arrest but so far its mechanisms are controversy. In this study we examine the effects of cGMP on germinal vesicle breakdown in cumulus-enclosed oocytes and denuded oocytes. Spontaneous maturation was inhibited by a cGMP agonist, 8-Br-cGMP with concentration dependent manners both in cumulus-enclosed oocytes and denuded oocytes. The inhibitory effect was more severe in denuded oocytes than cumulus-enclosed oocytes. The Rp-8-Br-cGMP and Rp-pCPT-8-Br-cGMP did not severely block GVB compared to 8-Br-cGMP. The spontaneous GVB inhibitory effects were different by the existence of cumulus. Based on them it is suggested that the cumulus modulates the role of cGMP in GV arrest.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.6
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• pp.337-341
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• 2006

The present study was designed to investigate the protein expression of nitric oxide synthase (NOS) and guanylyl cyclase (GC) activity in ischemia/perfusion (I/R) renal injury in rats. Renal I/R injury was experimentally induced by clamping the both renal pedicle for 40 min in Sprague-Dawley male rats. The renal expression of NOS isoforms was determined by Western blot analysis, and the activity of guanylyl cyclase was determined by the amount of guanosine 3', 5'-cyclic monophosphate (cGMP) formed in response to sodium nitroprusside (SNP), NO donor. I/R injury resulted in renal failure associated with decreased urine osmolality. The expression of inducible NOS (iNOS) was increased in I/R injury rats compared with controls, while endothelial NOS (eNOS) and neuronal NOS (nNOS) expression was decreased. The urinary excretion of NO metabolites was decreased in I/R injury rats. The cGMP production provoked by SNP was decreased in the papilla, but not in glomerulus. These results indicate an altered regulation of NOS expression and guanylyl cyclase activity in I/R-induced nephropathy.