• International Journal of Oral Biology
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• v.40 no.4
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• pp.211-216
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• 2015

Nitric Oxide (NO) is an important signaling molecule in the nociceptive process. Our previous study suggested that high concentrations of sodium nitroprusside (SNP), a NO donor, induce a membrane hyperpolarization and outward current through large conductances calcium-activated potassium ($BK_{ca}$) channels in substantia gelatinosa (SG) neurons. In this study, patch clamp recording in spinal slices was used to investigate the sources of $Ca^{2+}$ that induces $Ca^{2+}$-activated potassium currents. Application of SNP induced a membrane hyperpolarization, which was significantly inhibited by hemoglobin and 2-(4-carboxyphenyl) -4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt (c-PTIO), NO scavengers. SNP-induced hyperpolarization was decreased in the presence of charybdotoxin, a selective $BK_{Ca}$ channel blocker. In addition, SNP-induced response was significantly blocked by pretreatment of thapsigargin which can remove $Ca^{2+}$ in endoplasmic reticulum, and decreased by pretreatment of dentrolene, a ryanodine receptors (RyR) blocker. These data suggested that NO induces a membrane hyperpolarization through $BK_{ca}$ channels, which are activated by intracellular $Ca^{2+}$ increase via activation of RyR of $Ca^{2+}$ stores.

• Korean Journal of Veterinary Research
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• v.39 no.5
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• pp.930-937
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• 1999

Atrial natriuretic peptide(ANP) is a hormone with potent natriuretic, diuretic and relaxing properties on vascular smooth muscle. Specific chemical modulator in response for the ANP secretion has not been found yet. Therefore, we have investigated the role of $Ca^{2+}$ responsible for the regulation of ANP induced by protein kinase C(PKC) on mechanically stretch-induced ANP secretion in the rat atria. The results obtained were as follows ; 1. ANP secretion and ANP concentration were increased to more in $Ca^{2+}$-free buffer than in the Kreb-Henseleit buffer on mechanically stretch-induced ANP secretion(p < 0.05), but extracellular fluid translocation(ECF) was not significant. Phorbol 12-myristate 13-acetate(PMA, $10^{-7}M$) induced ANP secretion and ANP concentration in $Ca^{2+}$-free buffer shown to more accentuate on mechanically stretch-induced ANP secretion than in the $Ca^{2+}$-free buffer(p < 0.05), but ECF translocation was not significant. 2. In the presence of ryanodine($3{\times}10^{-6}M$), PMA($10^{-7}M$) induced ANP secretion and ANP concentration in the Kreb-Henseleit buffer were shown to more increase on mechanically stretch-induced ANP secretion than in the ryanodine($3{\times}10^{-6}M$) with the Kreb-Henseleit buffer(p < 0.05), but ECF translocation was not significant. 3. In the presence of ryanodine($3{\times}10^{-6}M$), PMA($10^{-7}M$) induced ANP secretion and ANP concentration in the $Ca^{2+}$-free buffer was shown to more increase on mechanically stretch-induced ANP secretion than in the ryanodine($3{\times}10^{-6}M$) with the $Ca^{2+}$-free buffer on mechanically induced ANP secretion(p < 0.05), but ECF translocation was not significant. The results suggest that PKC-induced ANP secretion may not be related to the change of $Ca^{2+}$ on mechanically induced ANP secretion in the rat atria.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.153.2-154
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• 2003

Pathophysiological elevation of intracellular calcium concentration ([$Ca^{2+}$]$_i$) in the neuron has been considered as an important responsible factor in the neuronal cell damages. However, the mechanism of increase of [$Ca^{2+}$]$_i$ through ryanodine receptor (RyR), the relationship between [$Ca^{2+}$]$_i$ level and cell damages have not been fully demonstrated. (omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.55-55
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• 1999

Imperatoxin A (IpTx$_{a}$), a 3.7 kDa peptide from the African scorpion Pandinus imperator, has been known as an agonist of skeletal ryanodine receptor (RyR). In order to study the structure and function of the toxins on RyR, the IpTx$_{a}$ cDNA was PCR-amplified using 3 pairs of primers and the toxin was expressed in E. coli expression system.(omitted)ted)

• The Journal of Korean Physical Therapy
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• v.19 no.5
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• pp.65-76
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• 2007

Purpose: It is generally accepted that smooth muscle contraction is triggered by intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) released from intracellular $Ca^{2+}$ stores such as sarcoplasmic teticulum (SR) and from the extracellular space. The increased $[Ca^{2+}]^i$ can phosphorylate the 20,000 dalton myosin light chain $(MLC_{20})$ by activating MLC kinase (MLCK), and this initiates smooth muscle contraction. In addition to the $[Ca^{2+}]_i$MACK-tension pathway, a number of intracellular signal molecules, including mitogen-activated protein kinase (MAPK), protein kinase C (PKC) and others, play important roles in the regulation of smooth muscle contraction. However, the mechanisms regulating contraction of depletion of SR $Ca^{2+}$ in mouse gastric smooth muscle strips is not still clear. Methods: To investigate the rotes of $Ca^{2+}$ influx and SR $Ca^{2+}$ release channel on gastric motility, isometric contraction and $[Ca^{2+}]_i$ were examined in mouse gastric smooth muscle strips. Results: High KCl, ryanodine, an activator of $Ca^{2+-}$induced $Ca^{2+}$ release channel, and cyclopiazonic acid (CPA), an inhibitor of SR $Ca^{2+-}$ATPase evoked a sustained increase in muscle contraction and $[Ca^{2+}]_i$. These increases induced by high KCl, ryanodine, and CPA were partially blocked by application of verapamil ($10{\mu}M$), a L-type $Ca^{2+}$ channel inhibitor. Additionally, in $Ca^{2+-}$free solution (1 mM EGTA), ryanodine and CPA had no effect contraction and $[Ca^{2+}]_i$ in fundic muscle strips. Conclusion: These results that extracellular $Ca^{2+}$ influx and depletion of SR trigger $Ca^{2+}$ influx through verapamil-sensitive $Ca^{2+}$ channel, and extracellular and SR $Ca^{2+}$ store may functionally involve in the subcellular $Ca^{2+}$ mobilization in mouse gastric muscle.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.9
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• pp.1244-1249
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• 2010

Comparisons of properties between skeletal ryanodine receptor 1 (sRyR1)-heterozygous-mutated and normal types of meat were carried out in pigs using PSE (pale, soft and exudative) meat found during the butchering process. All samples considered to be PSE meat showed irregular running and disorder of the muscle fibers and a wider inter-fiber space upon light microscopic observation. Electron microscopy revealed disintegration, twisting, and disorder of the myofibril arrangement and elimination of the Z line in PSE meat, compared with normal meat. Meat property tests demonstrated greater decreases in water holding capacity, moisture and sarcoplasmic protein, and higher $L^*$ values for the meat color index in PSE meat than in normal meat, but there were no differences in these factors between genetically normal and sRyR1-heterozygous PSE meat. On the other hand, higher $a^*$ and $b^*$ values were observed in sRyR1-heterozygous than in normal PSE meat, and similar alterations to the a* value were observed in terms of the amount of myoglobin and density of the 17-kDa protein band, corresponding to the molecular mass of myoglobin, on SDS-PAGE gels. These results suggest that sRyR1-heterozygous PSE pork contains much more myoglobin than genetically normal PSE meat.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.313-322
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• 1998

In a myocyte freshly isolated from rabbit cerebral artery, the characteristics of $Ca^{2+}$ release by histamine or caffeine were studied by microspectrofluorimetry using a $Ca^{2+}-binding$ fluorescent dye, fura-2. Histamine (5 ${\mu}M$) or caffeine (10 mM) induced a phasic rise of cytoplasmic free $Ca^{2+}$ concentration $([Ca^{2+}]_C)$ which could occur repetitively with extracellular $Ca^{2+}$ but only once or twice in $Ca^{2+}-free$ bathing solution. Also, the treatment with inhibitor of sarcoplasmic reticulum $Ca^{2+}-ATPase$ suppressed the rise of $[Ca^{2+}]_C$ by histamine or caffeine. In $Ca^{2+}-free$ bathing solution, short application of caffeine in advance markedly attenuated the effect of histamine, and vice versa. In normal $Ca^{2+}-containing$ solution with ryanodine (2 ${\mu}M$), the caffeine-induced rise of $[Ca^{2+}]_C$ occurred only once and in this condition, the response to histamine was also suppressed. On the other hand, in the presence of ryanodine, histamine could induce repetitive rise of $[Ca^{2+}]_C$ while the amplitude of peak rise became stepwisely decreased and eventually disappeared. These results suggest that two different $Ca^{2+}-release$ mechanisms (caffeine-sensitive and histamine-sensitive) are present in rabbit cerebral artery myocyte and the corresponding pools overlap each other functionally. Increase of $[Ca^{2+}]_C$ by histamine seems to partially activate ryanodine receptors present in caffeine-sensitive pool.

• Korean Journal of Veterinary Research
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• v.42 no.1
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• pp.65-71
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• 2002

We have utilized the PCR-RFLP method to detect the ryanodine receptor(RYR1) gene mutation and to estimate the genotype frequencies of the RYR1 gene in commercial crossbred pig population. The exon region(659bp) including point mutation(C ${\rightarrow}$T; Arg ${\rightarrow}$Cys) in the porcine ryanodine receptor gene, which is a causal mutation for PSS, was amplified by PCR and digested with Cfo I restriction enzyme. The RYR1 gene was classified into three genotypes by agarose gel electrophoresis. The normal homozygous(NN) individuals showed two DNA fragments consisted of 493 and 166bp. The mutant homozygous(nn) individuals showed only one DNA fragment of 659bp. Also, all three fragments(659, 493 and 166bp) were showed in heterozygous(Nn) carrier animals. The proportions of normal, carrier and PSS pigs within crossbred population of pigs were 81%, 15% and 4%, respectively. According to the results of analysis of variance for the association of genotypes of RYR1 of pigs at 30kg, day age at 90kg and average daily gains, the RYR1 nn genotype was very higher than RYR1 NN genotype for day age at 30kg with 5% level of significant difference, but no significant difference for association of any other genotypes with day age at 90kg and average daily gain in crossbred pigs. Therefore, DNA diagnosis by using PCR-RFLP analysis for the PSS gene was useful for large-scale screening of commercial pigs in the swine industry.

• Korean Journal of Animal Reproduction
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• v.21 no.3
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• pp.303-310
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• 1997

소 난포란의 체외성숙시 성숙배지에 FSH 및 LH의 첨가가 체외성숙난자의 calcium 반응과 체외수정란의 발달에 미치는 영향을 조사하였다. 난포란의 체외성숙은 TCM199을 기초로 한 4가지의 배양조건 하에서 : 1) 0.5$\mu\textrm{g}$/ml FSH＋5$\mu\textrm{g}$/ml LH, 2) 0.5$\mu\textrm{g}$/ml FSH, 3) 5$\mu\textrm{g}$/ml LH 및 4) 무 호르몬 첨가구로서 5% CO2에 24시간 동안 체외성숙을 유도하였다. 체외성숙 24기간째에 난포란의 과립막세포는 1ml PB1＋에서 4분 동안 vortexing을 하여 완전히 제거하였다. 세포 내 calcium 반응을 측정하기 위하여 2mM Fura-2 AM ester 및 0.02% Pluronic F-127가 첨가된 PB1-용액에 39$^{\circ}C$ in cubator에서 40분 동안 배양하였다. 30${\mu}\ell$ M2 medium drop을 30mm plastic dish에 만들어 20$\times$ 형광대물렌즈가 장착된 Nikon Diaphot 현미경의 장착된 Nikon Diaphot 현미경의 warm stage에 설치하였다. 세포 내 calcium 방출을 자극하기 위하여 난자에 25mM inositol 1, 4, 5-trasphophate(IP3)로 1.21kV/cm의 전기자극 또는 20mM ryanodine으로 미세주입을 실시하였다. 이러한 처리를 하지 않은 난자는 체외수정 후 CR1aa와 BRL monolayers의 공배양조건 하에서 체외발달을 유도하였다. 분할율(Day 2)과 배반포기발달율(Day 9)을 조사하였다. FSH와 LH의 처리구에서 IP3 또는 ryanodine으로 자극된 난자(1.79$\pm$0.05, 1.66$\pm$0.06)는 FSH, LH 및 무 호르몬처리구에 비하여 유의적으로 높은 calcium 반응을 보였다(1.00$\pm$0.03, 1.28$\pm$0.04, and 0.53$\pm$0.02 in IP3 elctroporation; 0.68$\pm$0.05, 1.03$\pm$0.05, and 0.47$\pm$0.04 in ryanodine microinjection). FSH와 LH, FSH, LH처리구에서 분할율(87.9, 71.5 및 75.6%)은 무 호르몬처리구(60.7%)(P<0.05)에 비하여 유의적으로 높았으며, FSH와 LH처리구(29.3%)에서의 배반포기 발달율은 FSH, LH 처리구뿐만 아니라 무 호르몬처리구보다 유의적으로 높았다(16.5, 19.0 and 9.8%)(P<0.05). Bovine FSH 및 Ovine FSH의 처리구에서의 calcium 반응은 유의적인 차이가 없었다(1.72$\pm$0.05, 1.61$\pm$0.06). 또한 분할율(82.2 and 84.0%) 및 배반포기(27.8 and 27.1%) 발달율도 bovine 및 ovine FSH처리구간에는 유의적인 차이가 없었다. 이상의 결과에서 전기자극에 의한 세포 내 calcium 반응은 체외성숙배지에 첨가하는 호르몬의 처리에 따라서 유의적인 변화를 보였다. 비록 분할율은 처리구간에 유의적인 차이가 없었지만 배반포기 발달율은 FSH와 LH 공동처리구에서 FSH, LH 단독처리구 및 무 호르몬처리구에 비하여 유의적으로 높은 발달율을 보였다. 체외성숙기간에 FSH와 LH의 공동첨가는 체외성숙 및 체외발달의 생리적인 교정을 위하여 요구되는 것으로 사려된다.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.413-419
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• 2016

Ryanodine receptors (RyRs) regulate the contractions of insect muscles by altering intracellular $Ca^{2+}$ concentration and are the targets of chlorantraniliprole. Recently, a chlorantraniliprole-resistant strain was reported in the diamondback moth Plutella xylostella by obtaining point mutations on the RyRs. In the present study, we established two resistant strains from Drosophila melanogaster, which were treated with low or high concentrations of chlorantraniliprole, and their resistance levels were determined on the basis of contact and ingestion toxicities. Compared with the control strain, the two resistant strains did not show any significant differences in contact toxicity. However, they showed significantly increased resistance ratios in ingestion toxicity than that by the control strain. The low and high concentration resistant strains exhibited 2.1- and 8.1-fold increased resistance ratios, respectively, compared with that by the control strain. Moreover, we found that the resistant strains had altered expression levels of RyRs and more enhanced Acetylcholinesterase and Glutathione-S-transferase activities than that by the non-selected strain. These results suggested that the resistance development of chlorantraniliprole in the two strains might be mediated by the activation of detoxification pathways in D. melanogaster.