• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.772-776
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• 2004

Physiological and molecular characteristics of Bacillus thuringiensis SR6 and SR8 were investigated, and phase contrast and electron microscopies revealed that a large rhomboidal crystal protein was present in the sporulating cells. SDS-PAGE and Western blot analyses showed that B. thuringiensis SR8 produced 70 kDa protein much more than other proteins, and that the 70 kDa protein could bind to the antibody of B. thuringiensis subsp. tenebrionis-crystal toxin protein, indicating that the crystal 70 kDa protein has an immunological homology with B. thuringiensis subsp. tenebrionis-crystal toxin protein. The DNA fragment of B. thuringiensis subsp. tenebrionis-toxin gene was detected in B. thuringiensis SR6 and SR8 by using PCR amplification analysis. Furthermore, the insect bioassay showed the insecticidal activity against Colorado potato beetle larvae. Based on the physiological and molecular similarities to B. thuringiensis subsp. tenebrionis, it is suggested that the B. thuringiensis SR6 and SR8 may be mutants of the B. thuringiensis subsp. tenebrionis strain overexpressing the crystal of 70 kDa toxin protein.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.6
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• pp.725-732
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• 1998

In order to elucidate the molecular mechanism of the intracellular $Ca^{2+}$ overload frequently reported from diabetic heart, diabetic rats were induced by the administration of streptozotocin, the membrane vesicles of junctional SR (heavy SR, HSR) were isolated from the ventricular myocytes, and SR $Ca^{2+}$ uptake and SR $Ca^{2+}$ release were measured. The activity of SR $Ca^{2+}-ATPase$ was $562{\pm}14$ nmol/min/mg protein in control heart. The activity was decreased to $413{\pm}30$ nmol/min/mg protein in diabetic heart and it was partially recovered to $485{\pm}18$ nmol/min/mg protein in insulin-treated diabetic heart. A similar pattern was observed in SR $^{45}Ca^{2+}$ uptakes; the specific uptake was the highest in control heart and it was the lowest in diabetic heart. In SR $^{45}Ca^{2+}$ release experiment, the highest release, 45% of SR $^{45}Ca^{2+}$, was observed in control heart. The release of diabetic heart was 20% and it was 30% in insulin-treated diabetic heart. Our results showed that the activities of both SR $Ca^{2+}-ATPase$ and SR $Ca^{2+}$ release channel were decreased in diabetic heart. In order to evaluate how these two factors contribute to SR $Ca^{2+}$ storage, the activity of SR $Ca^{2+}-ATPase$ was measured in the uncoupled leaky vesicles. The uncoupling effect which is able to increase the activity of SR $Ca^{2+}-ATPase$ was observed in control heart; however, no significant increments of SR $Ca^{2+}-ATPase$ activities were measured in both diabetic and insulin-treated diabetic rats. These results represent that the $Ca^{2+}$ storage in SR is significantly depressed and, therefore, $Ca^{2+}-sequestering$ activity of SR may be also depressed in diabetic heart.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.46-46
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• 2001

Evidence has suggested that an anion channel blocker, 4, 4'-diisothiocyanatostilbene-2, 2' disulfonic acid (DIDS) could trigger Ca release from skeletal sarcoplasmic reticulum (SR) by binding to a 30 kDa SR protein. Since the high molecular weight $Ca^{2＋}$ release channel (CRC)/ryanodine receptor (RyR) is the main SR protein that conducts $Ca^{2＋}$ efflux in skeletal muscles, the relationship between CRC and the 30kDa protein remains to be elucidated.(omitted)

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.96-96
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• 2002

We examined the role of SR 144528 (N-[-(1S-endo-1,3,,3-trimethyl-bicycle[2, 2, 1 ] heptan-2-y1]-5-(-4-chloro-3-mothyl-phenyl)-(4-methylbenzyl)-pyrazole-3- carboxamide) in the modulation of certain AC isoforms in transiently transfected COS-7 cells. We found that CB2 in COS cells has a constitutive activity, and thus leading to inhibition of AC-V activity even in the absence of agonist. In addition, this constitutive modulation of AC is reversed by SR144528. It is now well established that several G protein-coupled receptors can signal without agonist stimulation(constitutive receptors). Inverse agonists have been shown to inhibit the activity of such constitutive G protein-coupled receptor signaling. Agonist activation of the G$\_$i/o/-coupled peripheral cannabinoid receptor CB2 normally inhibits adenylyl cyclase type V and stimulates adenylyl cyclase type II. Using transfected COS cells, we show here that application of SR144528, an inverse agonist of CB2, leads to a reverse action (stimulation of adenylyl cyclase V and inhibition of adenylyl cyclase II). This inverse agonism of SR144528 is dependent on the temperature, as well as on the concentration of the cDNA of CB2 transfected. Pertussis toxin blocked the regulation of adenylyl cyclase activity by SR 144528.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.2
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• pp.175-182
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• 1999

In the present study, the underlying mechanisms for diabetic functional derangement and insulin effect on diabetic cardiomyopathy were investigated with respect to sarcoplasmic reticulum (SR) $Ca^{2+}-ATPase$ and phospholamban at the transcriptional and translational levels. The maximal $Ca^{2+}$ uptake and the affinity of $Ca^{2+}-ATPase$ for $Ca^{2+}$ were decreased in streptozotocin-induced diabetic rat cardiac SR, however, even minimal amount of insulin could reverse both parameters. Levels of both mRNA and protein of phospholamban were significantly increased in diabetic rat hearts, whereas the mRNA and protein levels of SR $Ca^{2+}-ATPase$ were significantly decreased. In case of phospholamban, insulin treatment reverses these parameters to normal levels. Minimal amount of insulin could reverse the protein levels; however, it could not reverse the mRNA level of SR $Ca^{2+}-ATPase$ at all. Thus, the decreased SR $Ca^{2+}$ uptake appear to be largely attributed to the decreased SR $Ca^{2+}-ATPase$ level, which is further impaired due to the inhibition by the increased level of phospholamban. These results indicate that insulin is involved in the control of intracellular $Ca^{2+}$ in the cardiomyocyte through multiple target proteins via multiple mechanisms for the decrease in the mRNA for both SR $Ca^{2+}-ATPase$ and phospholamban which are unknown and needs further study.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.123-128
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• 2009

This study was conducted to evaluate the weight reduction effect of yeast hydrolysate-SR101. Thirty female college students participated in a 6 week weight control program. All subjects were randomly assigned to either the placebo group, YH-SR101 (yeast hydrolysate-SR101) group, or eX diet (product of yeast hydrolysate-SR101) group. The mean energy intake of the placebo group was 1445.2${\pm}$364.0 kcal (carbohydrate: 60.1%, protein: 25.6%, fat: 14.3%), while those of the YH-SR101 and the eX diet group were 1505.6${\pm}$296.2 kcal (carbohydrate: 60.5%, protein: 22.2%, fat: 14.8%) and 1353.8${\pm}$326.3 kcal (carbohydrate: 63.2%, protein: 20.9%, fat: 15.9%), respectively. The placebo group lost 0.19${\pm}$1.14 kg of body weight, while the treatment groups (YH-SR101 and eX diet) lost 1.13${\pm}$0.83 and 1.54${\pm}$0.74 kg of body weight, respectively. There were significant differences in the decrease in body weight between the placebo and the treatment group (p<0.05). There were also significant differences in the decrease in fat mass between the placebo and treatment group (p<0.05). Furthermore, the BMI of the YH-SR101 and the eX diet groups also differed significantly before and after the diet program (p<0.05). Additionally, the BMI and waist size reduction of the treatment groups (YH-SR101 and eX diet group) differed significantly when compared to the placebo (p<0.05). The reduction of the resting metabolic rate (RMR) blood glucose, total-cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride did not differ significantly among groups. Taken together, these findings indicate that consumption of yeast hydrolysate-SR101 and eX Diet may lead to decreased body weight and fat.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.125-136
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• 1994

To characterize the SR Ca-release channel protein complex of crustacean, $^{45}Ca-release,\;[^3H]ryanodine$ binding, and immunoblot studies were carried out in the crayfish and/or lobster skeletal sarcoplasmic reticulum. Bmax and affinity of crayfish SR to ryanodine were lower than those of lobster SR. AMP (5mM) increased $[^3H]ryanodine$ binding significantly in both vesicles (P<0.05). $Mg^{2+}$(5mM) or tetracaine(1mM) inhibited $[^3H]ryanodine$ binding significantly in both vesicles (P<0.001), but ruthenium red $(10\;{\mu}M)$ inhibited it moderately. In SDS polyacrylamide gel electrophoretic analysis of crayfish SR vesicles, there was a high molecular weight band that showed similar mobility with Ca-release channel protein of lobster skeletal SR, but more rapid mobility (HMWBr) than that of rabbit skeletal SR (HMWBS). Immunoblot analysis showed that polyclonal Ab to lobster skeletal SR Ca-release channel protein was react with HMWBr of crayfish skeletal SR, but not with that of HMWBs of rabbit skeletal SR. ^{45}Ca-release from crayfish skeletal SR vesicles was increased by the increase of extravesicular calcium from $1{\mu}M$ to 1mM. This Ca-release phenomenon was similar, but more sensitive in the low concentration of $Ca^{2+}$, compared to that from lobster SR vesicles. AMP (5mM) or caffeine (10mM) did not affect to $^{45}Ca-release.\;^{45}Ca-release$ was inhibited slightly ($3{\sim}8%\;by\;Mg^{2+}$) (5mM) or tetracaine (1mM), and moderately (23%) by high concentration of ruthenium red $(300\;{\mu}M)$. From the above results, it is suggested that SR Ca-release channel protein of crustacean has different properties from that of the rabbit, and similar properties between crayfish and lobster in functional and immunological aspects, but Ca-release via crayfish channel may be more sensitive to calcium.

• Korean Journal of Acupuncture
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• v.30 no.4
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• pp.281-288
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• 2013

Objectives : This study aimed to evaluate the effects of Stephaniae tetrandrae Radix Herbal-acupuncture(SR-HA) at KI10(Umgok) on nephritis induced by lipopolysaccharide(LPS) in rats. Methods : Male SD rats (n=32) were allocated to four groups; normal, LPS, saline, and SR-HA. The rats in the LPS, saline, and SR-HA groups were injected intra-peritoneally with LPS (2 mg/kg) to induce nephritis. The rats in the saline and SR-HA groups were treated with saline injection and SR-HA respectively at KI10 three times a week. To evaluate the effects of SR-HA at KI10 on nephritis in rats, the authors evaluated the numbers of WBC and neutrophils in blood, and the levels of creatinine, TNF-${\alpha}$, CINC-1 in serum, creatinine, total protein in urine and renal MPO. Results : SR-HA at KI10 significantly inhibited the increase of WBC and neutrophils in blood, TNF-${\alpha}$, CINC-1 in serum, creatine, total protein in urine and MPO in kidney of LPS-stimulated rats. Conclusions : SR-HA at KI10 may have therapeutic effects on nephritis in LPS-stimulated rats.

• BMB Reports
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• v.29 no.1
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• pp.22-26
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• 1996

Agents that activate or inhibit the $Ca^{2+}$ release channel in cardiac sarcoplasmic reticulum (SR) were tested for their abilities to affect the activity of the SR $Ca^{2+}$-ATPase. Vesicles of junctional SR (heavy SR, HSR) from terminal cisternae were prepared from porcine cardiac muscle by density gradient centrifugation. The steady-state activity of $Ca^{2+}$-ATPases in intact HSR vesicles was/$347{\pm}5\;nmol/min{\cdot}mg$ protein (${\pm}$ SD). When the HSR vesicles were made leaky, the activity was increased to $415{\pm}5\;nmol/min{\cdot}mg$ protein. This increase is probably due to the uncoupling of HSR vesicles. Caffeine (10 mM), an agonist of the SR $Ca^{2+}$ release channel, increased $Ca^{2+}$-ATPase activity in the intact HSR vesicle preparation to $394{\pm}30\;nmol/min{\cdot}mg$ protein. However, caffeine had no significant effect in the leaky vesicle preparation and in the purified $Ca^{2+}$-ATPase preparation. The effect of caffeine on SR $Ca^{2+}$-ATPase was investigated at various concentrations of $Ca^{2+}$. Caffeine increased the pump activity over the whole range of $Ca^{2+}$ concentrations, from $1\;{\mu}M$ to $250\;{\mu}M$, in the intact HSR vesicles. When the SR $Ca^{2+}$-ATPase was inhibited by thapsigargin, no caffeine effect was observed. These results imply that the caffeine effect requires the intact vesicles and that the increase in $Ca^{2+}$-ATPase activity is not due to a direct interaction of caffeine with the enzyme. We propose that the activity of SR $Ca^{2+}$-ATPase is linked indirectly to the activity of the $Ca^{2+}$ release channel (ryanodine receptor) and may depend upon the amount of $Ca^{2+}$ released by the channels.

• Journal of Ginseng Research
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• v.20 no.3
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• pp.274-283
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• 1996

In this study, the effects of red ginseng components [ginsenosides (total saponins and $Rg_1$) on the function of ryanodine receptor (RyR) -$Ca^{2+}$ release channel complex protein (named as RyR or $Ca^{2+}$ channel), a membrane protein in sarcoplasmic reticulum (SR) of rabbit skeletal muscle were examined at the SR vesicle's level and the molecular levels with Chaps-solubilized and purified $Ca^{2+}$ channel protein and with reconstituted proteoliposomes by dialysis. The results were as follows. 1. The binding of ryanodine known as inhibitor of muscle contraction to the RyR was decreased at the whole range of concentration ($10^2$~$10^7$%) by these two ginseng components. In heavy SR vesicles, Chaps-solubilized and purified $Ca^{2+}$ channel protein, and reconstituted vesicles, its maximal inhibition by total saponins was shown at the concentration of $10^3$, $10^3$%, and $10^5$% respectively, and by gin- senoside $Rg_1}$) each was $10^3$%, $10^3$%, and $10^4$%. 2. The release of $Ca^{2+}$ ion through $Ca^{2+}$ channel in heavy SR vesicles and reconstituted proteoliposomes was increased as a whole by these two ginseng components, and particularly maximal release by both of them was shown at the range of $10^4$~$10^6$%. These results were seemed to be caused by conformational change of $Ca^{2+}$ release channel protein (RyR) by red ginseng components [ginsenosides (total saponins and $Rg_1}$).