• Korean Journal of Veterinary Research
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• v.31 no.1
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• pp.123-130
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• 1991

The present study was performed to investigate the effect of Ca ion concentration on sperm viability and acrosome reaction rate and to evaluate the effect of treatments using caffeine and Ca-ionophore A23187 on acrosome reaction rate in frozen-thawed bull spermatozoa. Viabilities of in vitro capacitated bull spermatozoa at 0, 2.25 and 4.5 mM Ca ion concenrations were 21.00, 26.00 and 22.59%, respectively and significantly higher in Ca ion 2.25mM added group than Ca ion free group (p<0.05) and acrosome reaction rates of in vitro capacitated bull spermatozoa were 17.09, 52.15 and 47.92%, respectively and significantly high in Ca ion added groups(p<0.05). Viabilities in vitro capacitation by caffeine and Ca-ionophore A23187 in control, caffeine treated group, Ca-ionophore A23187 treated group and caffeine+Ca-ionophore A23187 treated group were 37.91, 27.67, 22.33 and 25.59%, respectively and significantly higher in control than treated groups(p<0.05), there were no significant differences among the treated groups, and acrosome reaction rates were 10.33, 37.92, 48.09 and 57.17%, respectively and there were significant differences among the groups(p<0.05), especially higher in caffeine+Ca-ionophore A23187 treated group than others.

• Journal of Embryo Transfer
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• v.22 no.1
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• pp.75-80
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• 2007

The objective of this study was to examine the optimal concentration and the exposure time of ethanol, Ca-ionophore, and strontium to achieve massive recipient oocytes in porcine. The cleavage (51.4% vs. $21.3{\sim}44.3%$) and embryo development rates (45% vs. $13.3{\sim}29.9%$) were significantly higher (p.0.05) in oocytes treated with 10% ethanol for 10 min than other treatments. The oocytes treated with 25mM Ca-ionophore for a minimum of 2min and 20mM strontium for a minimum of 6h showed significantly higher cleavage and embryo development rates than those of other treatments (P<0.05). Cleavage rate with duplicated ethanol treatment was significantly lower than those with ethanol alone (P<0.05). The cleavage rate and embryo development rates were significantly lower in duplicated strontium treatment than those in both alone and combination (P<0.05). But the cleavage and embryo development rates in treatment with Ca-ionophore were significantly higher in combined treatment (Ca-ionophore and cycloheximide) than those in single or duplicated treatment (P<0.05). These results might induce establishment of the optimal concentration and the exposure time on activation media to build up activation condition of porcine oocytes.

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.519-522
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• 1997

A series of new ligands having convergent dicarboxylic acid functions, based-upon Rebek's cleft-type ionophore, have been prepared and their ion binding properties were investigated by the competitive extraction and transport experiments. The main purpose of the modification was to increase the lipophilicity of the Rebek's ionophore, which was attempted by utilizing propyl analog of Kemp's triacid or by changing the bridging unit. Ionophores 5 and 6 were found to have a pronounced ion-binding property toward Ca2+ ion. The selectivity in competitive extraction of ionophore 5 at pH 9 for Ca2+ over Mg2+ and Sr2+ is 2.0 and 59.3, respectively. The selectivity in competitive transport of ionophore 5 for Ca2+ over Mg2+ and Sr2+ is 29.8 and 99.3, and that of ionophore 6 is 10.0 and 23.2, respectively.

• Journal of Nutrition and Health
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• v.21 no.3
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• pp.173-181
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• 1988

Various types of evidence suggest that some changes in cellular in cellular calcium may well signal the initiation of a chain of events leading to the physiological effects of the bone resorbing agents. The effects of 1,25-dihydorxycholecalciferol, $1.25\textrm{(OH)}_2\textrm{D}_3$, Ca ionophore A23187 and calcium antagonist, diltiazem on bone resprption and the cellular transport of Ca were investigated. Bone $^{45}\textrm{Ca}$ desaturation experiment was realized in isolated heterogenous rat bone cells after equilibrating the cells with $^{45}\textrm{Ca}$. Results of $^{45}\textrm{Ca}$ desaturation experiments were analysed by fitting the $^{45}\textrm{Ca}$ desaturation curve to a model of 2 exponential terms which indicated the presence of 2 exchangeable cellular calcium pools. $1.25\textrm{(OH)}_2\textrm{D}_3$ (0.5ng/$m\ell$) induced significantly bone resorption which was decreased by the physiological dose of diltiazeme(above 5nmol/$m\ell$) although it was ineffective alone. Ionophore A23187 (0.2$\mu\textrm{g}$/$m\ell$) decreased Ca release from bone but no additivity of effect with diltiazem(20nmol/$m\ell$) was observed. $1.25\textrm{(OH)}_2\textrm{D}_3$ (0.5ng/$10^{6}$ cells) had a moderate effect on the two kinetic phases of $^{45}\textrm{Ca}$ desaturation curve and these values were normalized when diltiazeme (20nmol/$10^{6}$ cells) was added along with $1.25\textrm{(OH)}_2\textrm{D}_3$. Ionophore($0.05\mu\textrm{g}$/$10^{6}$ cells) alone increased specifically the value of the slow turnover rate which was not affected by addition of diltiazem. The hypothesis concerning the involvement of calcium in bone resorption seems in fact to be verified in case of $1.25\textrm{(OH)}_2\textrm{D}_3$ but more unsettled for Ca inophore A23187.

• Analytical Science and Technology
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• v.6 no.3
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• pp.307-311
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• 1993

Ionophore, which contains 5-membered heterocyclic compound, was prepared. $Mg^{2+}$ was determined by salting-out technique using ionophore as a chelating reagent. After $Mg^{2+}$ was extracted into the acetonitrile layer as a Mg-$(Ionophore)_2$ complex from acetate buffered aqueous solution by salting-out extraction technique, absorbance of complex was recorded by atomic absorption spectrophotometry. Optimum pH was between 2.5 and 5.0 for extraction and 1:2([$Mg^{2+}$]/[ionophore]) complex were formed. The range of detection was 0.24ppm~2.4ppm and $Ca^{2+}$ and EDTA were interfered in the determination of $Mg^{2+}$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.349-354
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• 2014

Elevation of intracellular calcium ($Ca^{{+}{+}}$) triggers degranulation of mast cells by bypassing receptor activation. Flos Sophora japonica L. has been used as a natural dying source and has been reported to have biological activities such as anti-inflammatory and anti-allergic effects through $Fc{\varepsilon}RI$ and IgE crosslinking. In the present investigation, we report the regulatory effect of ethanolic extract of Flos Sophora japonica L. (S.F) on allergic mediators produced by $Ca^{{+}{+}}$ ionophore activation in mast cells. S.F significantly inhibited calcium ionophore (A23187)-induced interleukin (IL)-4 and tumor necrosis factor (TNF)-${\alpha}$ production as well as mast cell degranulation. Furthermore, administration of S.F suppressed allergic reactions in a 2,4-dinitrofluorobenzene (DNFB)-induced allergic dermatitis mouse model. Both oral administration and ear painting using 50 mg/kg of S.F significantly reduced levels of cytokines such as IL-4, TNF, and interferon-${\gamma}$ in ear tissues compared to the DNFB alone-treated group. Serum IgE level in the S.F-treated group also decreased compared to the DNFB alone-treated group. Weights of spleens and lymph nodes in the S.F-treated groups also decreased compared to the control group. Considering the data, we conclude that S.F mediates its anti-allergic effects not only through $Fc{\varepsilon}RI$ stimulation but also $Ca^{{+}{+}}$ influx in mast cells.

• Reproductive and Developmental Biology
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• v.35 no.1
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• pp.17-22
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• 2011

This study was designed to determine the effect of electric field strength, duration and fusion buffer in fusion parameters on the rate of membrane fusion between the somatic cell and cytoplast for Korean cattle (HanWoo) somatic cell nuclear transfer (SCNT) procedure. Following electrofusion, effect of 5 or $10\;{\mu}M$ $Ca^{2+}$-ionophore of activation treatment on subsequent development was also evaluated. Cell fusion rates were significantly increased from 23.1% at 20 V/mm to 59.7% at 26 V/mm and 52.9% at 27 V/mm (p<0.05). Due to higher cytoplasmic membrane rupture or cellular lysis, overall efficiency was decreased when the strength was increased to 30 V/mm (18.5%) and 40 V/mm (6.3%) and the fusion rate was also decreased when the strength was at 25 V/mm or below. The optimal duration of electric stimulation was significantly higher in $25\;{\mu}s$ than 20 and $30\;{\mu}s$ (18.5% versus 9.3% and 6.3%, respectively, p<0.05). Two nonelectrolyte fusion buffers, Zimmermann's (0.28 M sucrose) and 0.28 M mannitol solution for cell fusion, were used for donor cell and ooplast fusion and the fusion rate was significantly higher in Zimmermann's cell fusion buffer than in 0.28 M mannitol (91.1% versus 48.4%, respectively, p<0.05). The cleavage and blastocyst formation rates of SCNT bovine embryos activated by $5\;{\mu}M$ $Ca^{2+}$-ionophore was significantly higher than the rates of the embryos activated with $10\;{\mu}M$ of $Ca^{2+}$-ionophore (70.0% versus 42.9% and 22.5% versus 14.3%, respectively; p<0.05). This result is the reverse to that of parthenotes which shows significantly higher cleavage and blastocyst rates in $10\;{\mu}M$ $Ca^{2+}$-ionophore than $5\;{\mu}M$ counterpart (65.6% versus 40.3% and 19.5% versus 9.7%, respectively; p<0.05). In conclusion, SCNT couplet fusion by single pulse of 26 V/mm for $25\;{\mu}s$ in Zimmermann's fusion buffer followed by artificial activation with $5\;{\mu}M$ $Ca^{2+}$-ionophore are suggested as optimal fusion and activation methods in Korean cattle SCNT protocol.

• Journal of Animal Science and Technology
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• v.48 no.3
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• pp.353-360
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• 2006

This study was performed to investigate the effects of artificial stimulation on the increase of the oocyte activation, to evaluate the expression of cyclin B1 protein levels in enucleated mouse oocytes, and to investigate correlation between the oocyte activation and the cyclin B1 protein levels. The oocyte activation was induced by 7% ethanol (EtOH) or 10μg/ml Ca-ionophore with or without 10μg/ml cycloheximide (CH). The activation rate was significantly higher in both single (p<0.05) and combined (p<0.01) stimulated groups compared to control group. The cyclin B1 protein level was significantly reduced in both stimulated groups (p<0.05), except for EtOH+CH treatment group. The expression of cyclin B1 protein showed a higher negative correlation with activation rate in EtOH+CH (r=0.61, p<0.05) and Ca+CH (r=0.86, p<0.01) stimulation groups, but not in a both single stimulation groups. Taken together, it can be suggested that single (EtOH and Ca- ionophore) and combined (EtOH+CH and Ca+CH) stimulation increases the oocyte activation, especially combined stimulation, because it induces the degradation of cyclin B1 protein after artificial stimulation treatments in mouse oocytes.

• Clinical and Experimental Reproductive Medicine
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• v.32 no.4
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• pp.337-346
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• 2005

Objective: The oligosaccharide moieties of glycoproteins and proteoglycans have a vital function in blastocyst differentiation. Concanavalin (ConA), a lectin, is known to bind on the preimplantation embryos, especially on blastocyst. In this study, we investigated whether ConA can modulate the trophoblast development and about the regulating mediator. Also, we investigated whether expansion is enough for hatching procession of the mouse blastocyst. Method: Embryos were collected at 72 h post hCG injection and chemicals were treated after 24 h (96 hr post hCG injection). ConA or calcium ionophore A23187 were exposed to blastocyst and than analysis the developmental process for 48 hr. Intracellular free-$Ca^{2+}$ concentration in trophectoderm was measured with confocal laser microscope after exposing to ConA or calcium ionophore A23187. ConA-pretreated blastocyst exposed to the calcium ionophore A23187 and then analyzed the developmental process. Otherwise ouabain was treated to the blastocyst to block the $Na^+/K^+$-ATPase activity. Results: In contrast to the control blastocyst, the ConA-exposed blastocysts developed beyond the expansion stage with significantly high rate (90.4%) at 12 h post administration. ConA induced an increase the intracellular $Ca^{2+}$ concentration in trophectoderm. Calcium ionophore A23187 also stimulated expansion of blastocyst. Most of the control blastocysts developed to the hatching stage at 144 h post hCG injection. However, strongly 65% of the ConA-exposed embryos were arrested at expanded stage at same time point. The developmental progression rates to hatching stage of both ConA- and calcium ionophore A23187-expose blastocysts were significantly lower than that of the control. However ConA-pretreated embryos developed to the hatching stage like control embryos. Ouabain showed a tendency to delayed the progress to expansion stage but did not inhibit the development to the hatching stage. Conclusion: ConA-mediated expansion is the result of the increase of intracellular free-calcium in blastocyst stage embryo. It is suspected that expansion of the blasocyst is a essential indirect factor in hatching and the calcium may triggering the cellular mechanisms for the both expansion and hatching progression.

• Clinical and Experimental Reproductive Medicine
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• v.19 no.2
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• pp.105-116
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• 1992

The present study was examined to clarify the role of calcium ion as a factor for the maturation of mouse oocytes. Follicles and cumulus-enclosed oocytes were isolated with two sharp needles under a stereomicroscope from female mouse (ICR) ovaries which were treated PMSG 5 IU 45-46 hours previously. Isolated follicles and cumulus-enclosed oocytes were cultured for 14-16 hours in an organ culture system at $37^{\circ}C$, 5% $CO_2$ in air and 100% humudified in incubator. MHBS was the basic medium used from which A23187, verapamil, $NiCl_{2.}$ $6H_2O$ and $LaCl_{3.}$ $7H_2O$ were added depending on the experimental groups. In follicle- or cumulus-enclosed oocytes wre cultured in these differently treated media. Following results were obtained from the present study. 1. The calcium ionophore A23187 directly or indirectly seems to stimulate GVBD of follicle-enclosed mouse oocytes. Increasing concentration of ionophore A23187 1ed to an increase in oocytes degeneration from the cumulus-enclosed mouse oocytes. 2. The organic $Ca^{++}$ channel blocker, verapamil does not induce GVBD of follicle-enclosed mouse oocytes. Specially, higher dose of 1 mM verapamil induced GVBD of follicle-enclosed mouse oocytes. However, cytoplasm of GVBD oocytes in 1 mM verapamil treated groups appeared shrunk. In the cumulus-enclosed oocytes, polar body formation was reduced in verapamil treated groups and degeneration increased. Verapamil inhibit oocyte maturation (polar body formation). 3. The $Ca^{++}$ inhibitor, Nickel ($NiCl_{2.}$ $6H_2O$) inhibits maturation of the follicle-enclosed oocytes. In the cumulus-enclosed oocytes the progression to MII (PB formation) was reduced and degeneration of mouse oocytes increased as the concentration of $Ni^{++}$ increase. The results indicates that nickel act as an inhibitor of calcium. 4. The $Ca^{++}$ inhibitors, Lanthanum ($LaCl_{3.}$ $7H_2O$) has shown different effect from that of nickel. In follicle-enclosed oocytes, 0.01mM lanthanum induced maturation of mouse oocytes. Polar body formation was reduced in the cumulus-enclosed oocytes all lanthanum treated group.