• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.244-251
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• 2001

Over half of all biologically active peptide and peptide hormones are $\alpha$-amidated at their C-terminus, which is essential for their full biological activities. Amidation is accomplished through the sequential reaction of the two enzymes encoded by the single bifunctional, peptidyl-glycine $\alpha$-amidating monooxygenase (PAM or an $\alpha$-amidating enzyme). PAM catalyze the forma - tion of a peptide amide from peptide precursors that include a C-terminal glycine, and requires copper molecular oxygen and ascorbate. PAM is the only enzyme that produces peptide amides in vivo. However various strategies utilizing PAM, carboxypeptidase-Y enzymes, and chemical syn-thesis have been developed for producing peptide amides in vitro. The growing need and impor-tance of peptide amide drugs has highlighted the necessity for a efficient in vitro amidating sys-tem for industrial application for the production of peptide hormones, like calcitonin and oxytocin. This review presents the current situation regarding amidation with a special emphasis on the in-dustrial production or peptide hormones.

• Biomolecules & Therapeutics
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• v.8 no.1
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• pp.99-106
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• 2000

Aspalatone [3-(2-methyl-4proponyl)]-2-acetyloxybenzoate, CAS 147249-33-0) is a compound having an antithrombotic action. General pharmacological properties of aspalatone were studied. Aspalatone had no effect on central nervous system and no anticonvulsant effect up to 1200 mg/kg p.o. However, the compound has hypothermic and analgesic effect. When administered intravenously in rabbits, aspalatone did not affect blood pressure, heat rate and respiration rate and depth, and it did not inhibit transient hypotensive effect of acetylcholine. The compound did not affect isolated guinea-pig ileum and tracheal strip at a concentration of 1${\times}$$10^{-4}$, and did not inhibit histamine-induced contraction of guinea-pig ileum. It also did not affect isolated rat stomach fundus and estrogenated rat uterus at 1${\times}$$10^{-4}$, and did not inhibit contraction produced by acetylcholine or oxytocin. The pupil size and intestinal propulsion were not influenced at a large dose of was shown. The compound showed a slight increase in urine volume and led to decreased excretion of potassium in urine of rats. The results suggest that aspalatone may have no considerable adverse effects in general pharmacological aspect.

• The Journal of Korean Medicine
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• v.15 no.2 s.28
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• pp.269-280
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• 1994

To elucidate the effects of Onkyungtang. after oral administration of Onkyungtang water extract in mice and rats, acute toxicity. analgesic. sedative, estrogenic actions. action on isolated uterine muscle were measured. The results obtained were as follows: 1. The yield of water extract of Onkyungtang was 24.5%, minimum lethal dose was 4,000mg/kg, which rarely had the acute toxicity in mice and rats. 2. The analgesic effects of Onkyungtang by acetic acid induced writhing syndrome in mice were not remarkably observed. 3. The relaxant action of Onkyungtang on oxytocin induced contracted uterine muscle in estrogenized rats were not remarkably observed. 4. The sedative effects of Onkyungtang by hexobarbital sodium induced sleeping time in mice were remarked. 5. Administration of Onkyungtang caused remarkable increase in weight of rat's uterus.

• Mass Spectrometry Letters
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• v.1 no.1
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• pp.5-8
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• 2010

In the present study, collisionally-activated dissociation (CAD) experiments were performed under low energy collision conditions in six peptides containing a disulfide bond. Fragments produced as a result of the cleavage of a disulfide bond were obtained after CAD in four peptides (bactenecin, TGF-$\alpha$, cortistantin, and linearly linked peptide, Scheme 1) with basic amino acid residues. In contrast, the CAD analysis of two peptides with no basic residue (oxytocin and tocinoic acid) rarely produced fragments indicative of cleavage of a disulfide bond. These results are consistent with the mobile proton model suggested by the McLuckey and O'air groups (ref. 22 and 23); nonmobile protons sequestered at basic amino acid residues appear to promote the cleavage of disulfide bonds.

• The Korean Journal of Physiology
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• v.21 no.1
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• pp.35-46
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• 1987

It has been well known that estrogens stimulate the uterine contractility and progestins inhibit it. Then, one may expect that the uterine contractility and sensitivities to oxytocin (OT) and prostaglandin $F_{2{\alpha}}\;(PGF_{2{\alpha}})$ would be different among the estrus cycle. These hypotheses were tested using the mature female rat. Spontaneous isometric contractions of isolated uterine strips $(1{\times}0.3\;cm)$ from cyclic rats in various stages of the estrus cycle, bilateral ovarectomized rats and hypophysectomized rats were recorded in absence or presence with $estradiol-17{\beta}\;(E_2)$, progesterone $(P_4)$, OT and $PGF_{2{\alpha}}$. The results were summarized as follows: 1) The spontaneous uterine contractile force was the highest in the estrus rat and the lowest in the ovarectomized or the hypophysectomized rat. In the proestrus rat, the contractile frequency was the lowest (2.7 beats/10 min) and the contractile duration was the longest (70 sec). In the other groups, there were no any differencies in frequency (9 beats/10 min) and in duration (30 sec). 2) OT and $PGF_{2{\alpha}}$ stimulated the uterine contractility in all groups tested except in the hypophysectomized rat in which OT failed to stimulate the uterine contraction. $PGF_{2{\alpha}}$ was more effective in stimulating the uterine contraction than OT in all groups tested except in the estrus rat. OT-induced contraction was the highest in the estrus rat and $PGF_{2{\alpha}}-induced$ contraction was the lowest in the hypophysectomized rat. 3) Uterine contractilities were not changed by the in vitro treatments of $E_2$ or $P_4$ under the influence of endogenous steroids, however, $E_2$ and $P_4$ stimulated the uterine contraction in the ovarectomized rat in which endogenous steroids were almost abolished. 4) Increased uterine contraction by the treatment of OT was suppressed by in vitro $E_2$ or $P_4$ in the estrus rat, while it was potentiated by the $P_4$ in the proestrus rat. In other groups, exogenous $E_2$ or $P_4$ did not affect the OT-induced uterine contraction. 5) $PGF_{2{\alpha}}-induced$ uterine contraction was suppressed in the ovarectomized rat by $E_2$ and $P_4$, in the diestrus and proestrus rats by $P_4$ and in the hypophysectomized rat by $E_2$. In other groups, exogenous $E_2$ or $P_4$ was ineffective in altering the $PGF_{2{\alpha}}-induced$ uterine contraction. According to the above results, it may conclude that the mechanisms of the different uterine contractility and the different uterine sensitivity to OT or $PGF_{2{\alpha}}$ according to the estrus cycle are not explicable with only the serum concentrations of steroids, OT and $PGF_{2{\alpha}}$ but also other unknown factors.

• Journal of Life Science
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• v.26 no.2
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• pp.164-173
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• 2016

Isotocin (IT), a nonapeptide homolog of oxytocin in mammals, has been suggested to be involved in physiological processes including social behaviors, stress responses, and osmoregulation in teleost fish. To study its structure and function, the gene encoding the IT precursor was cloned from the genomic DNA and brain cDNA of the cinnamon clownfish, Amphiprion melanopus. The IT precursor gene consists of three exons separated by two introns, and encodes an open reading frame of 156 amino acid (aa) residues, comprising a putative signal peptide of 19 aa, a mature IT protein of 9 aa, a proteolytic processing site of 3 aa, and 125 aa of neurophysin. Tissue-specific analysis of the IT precursor transcript indicated its expression in the brain and gonads of A. melanopus. To examine its osmoregulatory effects, the salinity of the seawater (34 ppt) used for rearing A. melanopus was lowered to 15 ppt. Histological analysis of the gills indicated the apparent disappearance of an apical crypt on the surface of the gill lamella of A. melanopus, as pavement cells covered the surface upon acclimation to the lower salinity. The level of Na⁺/K^+-ATPase activity in the gills was increased during the initial stage of acclimation, followed by a decrease to its normal level, suggesting its involvement in osmoregulation and homeostasis. The only slight increase in the level of IT precursor transcript in the A. melanopus brain upon low-salinity acclimation suggested that IT played a minor role, if any, in the process of osmoregulation.

• Korean Journal of Veterinary Research
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• v.31 no.2
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• pp.137-142
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• 1991

This study was carried out to reconstruct three-dimensional plaster model of the supraoptic and paraventricular nuclei of 3 Korean native goats. The representative coronal sections of the hypothalami were stained immunohistochemically with monoclonal antibodies to vasopressin and oxytocin simultaneously. Plaster models were reconstructed by schematic drawings which were made by tracing onto the tracing paper with the aid of a drawing attachment. The results were as follows: The configurations of the models of 3 supraoptic nuclei were slender spherical shape at their cranial parts, and the highest and widest size at middle parts, and became lower and narrow at caudal parts in two models, hence one was directed dorsolaterally. The medial surfaces of the para ventricular nuclei were vertically flat, and lateral surfaces were more complex than medial with processes directed dorsolaterally at their cranial portion. They change positions dorsally at caudal portion, and there were no significant variations in shape between them.

• Korean Journal of Animal Reproduction
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• v.23 no.4
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• pp.365-369
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• 1999

Interferon tau (IFN$\tau$), the pregnancy recognition signal in ruminants, suppresses transcription of the estrogen receptor (ER) gene in the endometrial luminal (LE) and superficial glandular epithelium (sGE) to prevent oxytocin receptor (OTR) expression and pulsatile release of luteolytic prostaglandin $F_{2{\alpha}}$ (PGF), Interferon regulatory factors one (IRF-l) and two (IRF-2) are transcription factors induced by IFN$\tau$ that activate and silence gene expression, respectively. Available results suggest that IFN$\tau$ acts directly on LE and sGE during pregnancy to induce sequentially IRF-l and then IRF-2 gene expression to silence transcription of ER and OTR genes, block the luteolytic mechanism to maintenance a functional corpus luteum (CL) and, signal maternal recognition of pregnancy. The theory for maternal recognition of pregnancy in pigs is that the uterine endometrium of cyclic gilts secretes PGF in an endocrine direction, toward the uterine vasculature for transport to the CL to exert its luteolytic effect. However, in pregnant pigs, estrogens secreted by the conceptuses are responsible, perhaps in concert with effects of prolactin and calcium, for exocrine secretion of PGF into the uterine lumen where it is sequestered to exert biological effects and / or be metabolized to prevent luteolysis.

• The Journal of Korean Obstetrics and Gynecology
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• v.23 no.1
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• pp.12-29
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• 2010

Purpose: This study was conducted to investigate the effect on factors related lactation after administration of Palmul-tang in postpartum C57BL/6N mice. Materials and Methods: Experimental groups were divided into control group post-par group and pre-par group. Pre-par and post-par group were administered Palmul-tang(p.o) twice a week for 4 weeks or 3 weeks respectively. Control group was administered normal saline for 3 weeks. Then we observed morphological change, immunohistochemical density and milk protein gene expression of factors related lactation within mammary gland of postpartum mice. Results: In post-par and pre-par groups, adipose tissue within mammary gland significantly decreased, and ductal branch and alveoli prominently developed than that of control group at 1~3 weeks after administraion of Palmul-tang. In post-par and pre-par groups, density of immunoreactivity on oxytocin, prolactin, estrogen and progesterone receptors in mammary glandular tissue significantly increased than that of control group. mRNA expression of $\beta$-casein and placental lactogen (PL)-1 in post-par group was more increased than that of control and pre-par groups. Conclusion: These results suggest that Palmul-tang significantly improved factors related lactation at postpartum period.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.10a
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• pp.12-12
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• 2010

Nature applied flavanoids, glucosinolates and peptides for a great variety of functions. Flavanoids and glucosinolates are rich source of antioxidants, generally present in colored fruits and vegetables. Quercetin and its glucosides areone of the best examples of flavonol used in daily diet. Whereas peptides can act as antimicrobial, chemical messenger, neurotransmitter etc that regulating various life processes. Aspartame, a dipeptide is used as artificial sweetener and oxytocin for medical purposes, gained importance in everyday life. So, flavanoids, glucosinolates, peptides and their derivatives continue to hold the attention of synthetic chemists, agriculturists and biologists. Apart from a variety of naturally occurring bioactive metabolites, we are aiming to extract, separate and synthesize new analogs of promising natural drug candidates.