• 대한수의학회지
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• 제35권2호
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• pp.229-236
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• 1995

The effect of ${\alpha}_1$-adrenoceptor(${\alpha}_1$-AR) stimulation on intracellular pH($pH_i$), $Na^+$ activity($a_{Na}{^i}$) and contractility were investigated in isolated papillary muscles of euthyroid or hyperthyroid guinea pig with conventional microelectrode, $Na^+$ or $H^+$-selective microelectrodes, and tension transducer. Stimulation of the ${\alpha}_1$-AR by phenylephrine produced a decrease in $a_{Na}{^i}$ in euthyroid preparations. This decrease in $a_{Na}{^i}$ was abolished in presence of PKC activator, phorbol dibutyrate, and increased contrary to decrease. Phenylephrine also increased $a_{Na}{^i}$ in hyperthyroid ones. However, phenylrephtine produced an increase in $pH_i$ in both euthyroid and hyperthyroid ones. These changes were blocked by prazosin, an antagonist of ${\alpha}_1$-AR. These findings suggest that the changes in $a_{Na}{^i}$ and $pH_i$ are mediated by a stimulation of $Na^+-H^+$ exchange via ${\alpha}_1$-AR stimulation. This study focused on the increase in $a_{Na}{^i}$, $pH_i$ and contractility. The increase in $pH_i$ was blocked by amiloride or EIPA, $Na^+-H^+$ exchange inhibitors. Therefore, the increase in $a_{Na}{^i}$ and $pH_i$ mediated by ${\alpha}_1$-AR appeared to be due to an influx of $Na^+$ and a reduction of $H^+$ through $Na^+-H^+$ exchange. This study also revealed that the increase in $pH_i$ and $a_{Na}{^i}$ might be related to the sustained positive inotropic response. The $a_{Na}{^i}$ increase may contribute to the intracellular $Ca^{2+}$ through the $Na^+-Ca^{2+}$ exchange, and the $pH_i$ increase could cause an increase in the $Ca^{2+}$ sensitivity of myofilaments and may augment the ${\alpha}_1$-AR-mediated positive inotropic response.

• Asian-Australasian Journal of Animal Sciences
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• 제16권8호
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• pp.1131-1136
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• 2003

Forty-eight individually fed Angus steers (body weight $220kg{\pm}9.1$) were utilized to investigate the effects of copper (Cu) source and concentration on lipid metabolism and carcass quality. Steers were stratified by body weight and initial liver Cu concentration and randomly assigned to one of five groups. Groups were then randomly assigned to treatments. Treatments consisted of: 1) control (no supplemental Cu); 2) 10 mg Cu/kg DM from $CuSO_4$; 3) 10 mg Cu/kg DM from a Cu amino acid complex (Availa Cu) 4) 20 mg Cu/kg DM from $CuSO_4$; and 5) 20 mg Cu/kg DM from Availa Cu. Steers were fed a corn-alfalfa-based growing diet for 56 d. Steers were then switched to a high concentrate finishing diet for 145 d. On day 74 of the finishing phase subcutaneous adipose tissue biopsies were obtained from three steers/treatment to determine basal and stimulated lipolytic rates in vitro. Steers were then slaughtered after receiving the finishing diet for 145 d. Control steers tended (p<0.12) to have lower ceruloplasmin (Cp) activity than Cu supplemented steers. Steers receiving 20 mg Cu/kg DM from Availa Cu had higher (p<0.03) Cp activity than steers receiving 20 mg Cu/kg DM from $CuSO_4$. Plasma non-esterified fatty acids were similar across treatments. Steers receiving 10 mg Cu/kg DM from Availa Cu had higher (p<0.02) total plasma cholesterol concentrations relative to steers receiving 10 mg Cu/kg DM from $CuSO_4$. Steers receiving 20 mg Cu/kg DM from Availa Cu had lower (p<0.03) plasma triglyceride concentrations than steers supplemented with 20 mg Cu/kg DM from $CuSO_4$. Fatty acid profile of longissimus muscle was similar across treatments. Backfat depth tended (p<0.18) to be lower in Cu supplemented steers relative to controls. Steers supplemented with 20 mg Cu/kg DM from Availa Cu had heavier (p<0.03) hot carcass weights and a greater (p<0.02) dressing percentage than steers supplemented with 20 mg Cu/kg DM from $CuSO_4$. Furthermore, in vitro basal (p<0.06) and epinephrine stimulated (p<0.04) lipolytic rates of subcutaneous adipose tissue were higher in Cu supplemented steers relative to controls. The results of this study suggest that Cu supplementation has minimal effects on blood and lean tissue lipid profile. However, it appears that Cu may play a role in lipid metabolism in subcutaneous adipose tissue.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제20권4호
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• pp.341-354
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• 1998

GMI (Fibrel${(R)}$) is one of the dermal filling substances which have been successfully used for the treatment of depressed cutaneous scar and wrinkles. It's major components are; Gelatin powder, which provides a framework for the clot to form and remains stable under the scar, and ${\varepsilon}$-aminocaproic acid, which inhibits the production of fibrinolysin, and Plasma, which provides the necessary ingredients for collagen synthesis. GMI has advantages of low immunogenicity and increased longevity. It has been known to induce fibroblast activity and promote new collagen synthesis. We used 34 Sprague-Dawley rats which were bred under the same condition and duration. 18 of experimental animals were undergone cardiac puncture, and their blood were collected, centrifugated, and stored in freezer. Out of 16 animals, control group were injected with 2ml plasma into the subcutaneous tissue of Lt. scapular, while experimental group were implanted of 2 ml GMI into the Rt. same area. Experimental animals were sacrificed at the 3rd day, 5th day, 1st week and 2nd week respectively after implantation of GMI. To observe the histopathologic change of GMI and surrounding tissue reaction of GMI, we had examined with H&E staining, immunohistochemical staining with vimentin, ${\alpha}$-SMA, S-100 under LM and SEM. The obtained results were as follows ; 1. In LM study, the inflammatory cell infiltrations and granulation tissue formation were observed, and muscle tissues were well attached with adipose tissues in the control group. In the experimental group, inflammatory cell infiltrations had been observed by the 2nd week and irregular adipiose tissues and well differentiated mesenchymal tissues were examined. 2. In immunohistochemical study, the experimental group of ${\alpha}$-SMA study, there were a prominent positive response on endothelial development of granulation tissues and mesenchymal tissues compare with the control group. In vimentin study, positive response on mescenchymal fibroblast continued to 2nd week, but negative in the control group. In S-100 study, both groups were positively responded on irregular adipose tissues. 3. In SEM study, collagen fibers were embedded by the plasma by the 5th day in the control group, and in the 3rd day experiment GMI were resorved but communited with collagen fiber till the 1st week. Collagen fibers were infilt-rated into GMI at the 2nd week and the infilltrated GMI were conglomerated with the mature adipose cells and the collagen fibers. From the above results, GMI implantation in the subcutaneous tissue of Sprague-Dawley rat, the mild infiltration of inflammatory cells were showed till 2nd week and the granulation tissues were observed. GMI were nearly resorbed till 2nd week, but well attached with adipose tissue and collagen fibers. The endothelium and fibroblasts were actively proliferated. Adipose tissues and mesenchymal tissue cells were observed. As already expressed, GMI showed resorptive change in course of time without any early immune reaction, and seemed to induce fibroblast activity and promote new collagen synthesis.

• 대한의용생체공학회:의공학회지
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• 제23권2호
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• pp.109-117
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• 2002

위전도(EGG electrogastrography)는 비관혈적으로 복부에 전극을 부착하여 위에서 발생하는 위 근육의 전기적인 활동성(gastric electrical activity)을 측정하는 방법이다. 위전도 신호는 주파수가 매우 낮으며(0.0083~0.15 Hz) 진폭이 매우 작기(10~100 uV) 때문에 잡음의 영향을 많이 받게 된다. 이로 인해 FIR(finite impulse response) 필터나 IIR(infinite impulse response) 필터에서는 위전도 신호와 같이 0.1417 Hz의 좁은 대역폭을 가지는 신호를 필터링하기 위해서는 높은 차수로 인해 불안정해지거나 신호가 왜곡되는 경우가 발생한다. 그래서 본 연구에서는 Daubechies 모웨이브렛을 7단계로 확장한 웨이브렛 다단계 분해 필터를 사용하였으며 기존에 많이 사용되는 2종류의 FIR 필터, 4종류의 IIR 필터들을 신호대 잡음비(SNR : signal to noise ratio)과 재생신호 자승오차(RSE : reconstruction squared error) 등의 파라미터를 이용하여 시뮬레이션 위전도 신호를 이용하여 성능을 평가하였다. 정규분포임의잡음(normal distribution random noise)이 합성된 시뮬레이션 위전도 신호를 사용한 웨이브렛 다단계 분해 필터의 SNR은 비교대상이 된 필터들 중, 최고의 SNR에 비해 잡음의 레벨에 따라 각각 9.5, 6.9, 4.7 dB 더 좋은 성능을 보여주었다. RSE에서도 $1.22{\times}10^6, 1.16{\times}10^6, 1.02{\times}10^6$이 더 적은 에러를 보여주었다.

• The Korean Journal of Physiology and Pharmacology
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• 제5권5호
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• pp.397-405
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• 2001

The ryanodine receptor, a $Ca^{2+}$ release channel of the sarcoplasmic reticulum (SR), is responsible for the rapid release of $Ca^{2+}$ that activates cardiac muscle contraction. In the excitation-contraction coupling cascade, activation of SR $Ca^{2+}$ release channel is initiated by the activity of sarcolemmal $Ca^{2+}$ channels, the dihydropyridine receptors. Previous study showed that the relaxation defect of diabetic heart was due to the changes of the expressional levels of SR $Ca^{2+}$ATPase and phospholamban. In the diabetic heart contractile abnormalities were also observed, and one of the mechanisms for these changes could include alterations in the expression and/or activity levels of various $Ca^{2+}$ regulatory proteins involving cardiac contraction. In the present study, underlying mechanisms for the functional derangement of the diabetic cardiomyopathy were investigated with respect to ryanodine receptor, and dihydropyridine receptor at the transcriptional and translational levels. Quantitative changes of ryanodine receptors and the dihydropyridine receptors, and the functional consequences of those changes in diabetic heart were investigated. The levels of protein and mRNA of the ryanodine receptor in diabetic rats were comparable to these of the control. However, the binding capacity of ryanodine was significantly decreased in diabetic rat hearts. Furthermore, the reduction in the binding capacity of ryanodine receptor was completely restored by insulin. This result suggests that there were no transcriptional and translational changes but functional changes, such as conformational changes of the $Ca^{2+}$ release channel, which might be regulated by insulin. The protein level of the dihydropyridine receptor and the binding capacity of nitrendipine in the sarcolemmal membranes of diabetic rats were not different as compared to these of the control. In conclusion, in diabetic hearts, $Ca^{2+}$ release processes are impaired, which are likely to lead to functional derangement of contraction of heart. This dysregulation of intracellular $Ca^{2+}$ concentration could explain for clinical findings of diabetic cardiomyopathy and provide the scientific basis for more effective treatments of diabetic patients. In view of these results, insulin may be involved in the control of intracellular $Ca^{2+}$ in the cardiomyocyte via unknown mechanism, which needs further study.

• 대한한방내과학회지
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• 제29권1호
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• pp.117-129
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• 2008

Background & Objective : Naeso-san(NSS) has been used for the treatment of functional dyspepsia, regarded as a gastric dysmotility disease. A main cause of gastric dysmotility is antral dilatation or antroduodenal uncoordination. Therefore, we investigated the effect of NSS on gastric motility and its mechanism of action, as well as the morphologic changes in antral dilatated rats. Methods : Antral dilatated rats were induced by wrapping a nonabsorbable rubber ring(D:6mm, W:4mm, T:1mm) around the 1st portion of the duodenum for 8 weeks. Then morphologic changes were investigated and compared with normal intact rats before and after 8 weeks. Gastric emptying was measured by administration of normal saline(NS) or NSS in normal intact and antral dilatated rats. In another series of experiments to evaluate the mechanism of NSS under delayed conditions, normal intact rats were treated with atropine sulfate(1mg/kg, s.c.), quinpirole HCl(0.3mg/kg, i.p.), $NAME(N^{G}-nitro-L-arginine$ methyl ester, 75mg/kg, s.c.) and cisplatin(10mg/kg, i.p.), respectively. The myoelectrical activity of the gastric smooth muscle was recorded in normal intact and antral dilatated rats. The contractile waves were measured for 30 minutes before and after administration of each solution(NS, NSS). Results : Body weight gain of antral dilatated rats was significantly lower than that of the controls. Futhermore, we found the thickness of the mucosal and muscular layers and surface area of the stomach increased significantly compared with controls. NSS 278㎎/㎏ improved gastric emptying more than normal saline or NSS 93mg/kg in normal intact(p=0.026) and antral dilatated rats(p=0.03). NSS enhanced gastric emptying significantly in the NAME treated group(p=0.002). NSS 278mg/kg increased the significant postprandial dominant power than that of NS in normal intact rats, whereas there was no statistical significance in antral dilatated rats. Conclusions : NSS stimulates gastric motility through the cholinergic pathway. We expect that pathologic model with antral dilatation can be used as an exprimental tool which is similar to dyspepsia and NSS would be effective especially in dysmotility-like functional dyspepsia with antral dilatation or impaired reservoir functions such as gastric adaptive relaxation.

• Journal of Oral Medicine and Pain
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• 제26권1호
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• pp.39-50
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• 2001

In order to investigate the effect of Transforming growth factor ${\beta}1$(below TGF-${\beta}1$) and osteogenic protein-1(below Op-1) onto the myogenic differentiation, C2C12 satellite myoblastic cell line was cultured and treated with both growth factors. At first morphological changes with microscopical examination were examined, and isolated total RNA to analyse mRNA expression of bone marker proteins, muscle regulatory proteins, TGF-${\beta}$ receptor and their ligands by Northern blot analysis. And cellular proliferative inducibility of both growth factors was also tested to C2C12 cells. Incubating the cell with $5ng/m{\ell}$ of TGF-${\beta}1$ until 4 days almost inhibited multinucleated myotube formation expressing muscular regulatory proteins, and induced decreasing Id proteins. However, no osteoblastic phenotypes was induced by TGF-${\beta}1$ in C2C12 cells. The mRNA expression of TGF-${\beta}$ receptors with TGF-${\beta}1$ was conversed after 48 hours cultured. Type I TGF-${\beta}$ receptor was seemed to play a role in negative signalling for inhibition of myogenic differentiation. OP-1 dose dependently induced ALP activity, osteopontine production and bone sialoprotein production at concentrations above $100ng/m{\ell}$ and osteocalcin production at concentrations above $300ng/m{\ell}$. The concentration of OP-1 required to induce these osteoblastic phenotypes was the same as that required to almost completely inhibit myotube formation. Incubation with above $100ng/m{\ell}$ OP-1 suppressed the expression of mRNA for muscular egulatory proteins from 2 days after incubation. Expression of Id-1, 2, 3 mRNA were stimulated by OP-1 at concentration above $300ng/m{\ell}$. When C2C12 cells were treated with both growth factors, TGF-${\beta}1$ potentiated the inhibitory effect of OP-1 on myotube formation and expression of mRNA for myogenin at 12 days. And TGF-${\beta}1$ reduced osteocalcin and bone sialoprotein production induced by OP-1 at 12 days in C2C12 cells. Both growth factor had no mitogenic effect. These results indicate that OP-1 converts the differentiation pathway of C2C12 myoblasts into that of osteoblastic lineage cells and it's not heritable, but TGF-${\beta}1$ does not and has reversible inhibitory activity on the myogenic differentiation. TGF-${\beta}1$ and OP-1 play a role in myogenic differentiation via different mechanism between them.

• 한국환경생태학회지
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• 제29권6호
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• pp.858-864
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• 2015

문둥이박쥐(Eptesicus serotinus)의 생후 발성발달 특징을 파악하기 위하여 임신한 암컷 3개체로부터 총 4개체의 새끼 박쥐를 확보하여 발성변화를 분석하였다. 녹음 및 분석은 생후 1일부터 40일까지 수행하였으며, 펄스 지속시간(PD), 펄스 간격(PI), 최고 주파수(PF), 시작 주파수($F_{MAX}$), 종료 주파수($F_{MIN}$), 대역폭(BW)에 대하여 측정하였다. 새끼 박쥐는 생후 초기에 가장 다양한 패턴의 음성을 발산하였으며, 연령이 증가함에 따라서 점차 어미와 유사해졌다. PD와 PI는 연령이 증가할수록 감소하였으며, 반면 PF, $F_{MAX}$, $F_{MIN}$, BW는 증가하였다. PF, $F_{MAX}$, $F_{MIN}$, BW는 생후 10일에서 20일 사이에 가장 큰 변화가 확인되었으며, PD는 생후 30일에서 40일 사이에 가장 큰 변화가 확인되었다. 따라서 진동수의 발성과 관련이 있는 발성근육의 수축 능력은 생후 20일경 가장 발달하게 되며, 발성시간과 관련된 발성근육의 이완 능력은 생후 30일에서 40일 사이에 가장 발달하는 것으로 판단된다. 본 연구에 이용된 새끼 개체들은 생후 40일차에도 비행이 확인되지 않았으나 발성음은 어미와 유사하게 나타났다. 따라서 이러한 결과는 새끼 박쥐의 발성 발달은 비행행동 또는 비행과 관련된 근육의 발달을 필수적으로 동반하는 것은 아니라는 것을 보여주는 결과라 판단된다.

• 대한치과교정학회지
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• 제18권1호
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• pp.189-207
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• 1988

In almost all biologic systems, mechanically induced electric charge separation is a fundamental phenomenon. Since the hypothesis was established that the generation of electric potentials in bone by mechanical stress including muscular force might control the activity in bone by mechanical stress including muscular force might control the activity of osseous cells and their biopolymeric byproduct, the concept of electrically mediate growth mechanism, which involves biological growth and bone remodeling by any means, in living systems has been applied clinically and experimentally to orthopedic fracture repair, the regulation of orthodontic tooth movement, epiphyseal cartilage regeneration, etc. On the other hand, recent numerous research data available show apparently that the mandibular condyle has the characteristics of growth center as well as growth site. In addition, there exists a considerable difference of opinion as to the role of external pterygoid muscle in condylar growth. In view of these evidences, this. experiment was performed to investigate the effect of the galavic current on the growth of the mandible and condyle for elucidating the nature of condylar growth. The bimetallic device was composed of silver and platinum electrode connected with resistor (3.9 Mohm), which was expected to produce galvanic current of 23.6 nA according to the galvanic principle. The 25 Sprague-Dawley rats were divided into two group, 2 week group comprising 8 animals exposed to satanic current for 2 weeks and 3 control animals not exposed for 2 weeks, 4 week group comprising 10 animals in experimental group and 4 animals in control group applied for 4 weeks respectively. The experimental rats were subjected to application of the galvanic current invasively to codylar head surface and the control groups with sham electrode. On the basis of anatomic and histologic data from the mandibular condyle of experimental and control group, the following results were obtained. 1. After 2 weeks, there was no increase of mandibular size in experimental group over that of the control group. 2. After 4 weeks, the size of the condylar head was larger in experimental group than that of the control. 3. In 2 week group, the thickness of the mitotic compartment and hypertrophic chondroblastic layer was increased in experimental group. 4. In 4 week group, the number and the size of the hypertrophic chondroblasts were increased significantly on experimental group over that of the control group. 5. The application of the satanic current caused an increase in chondrocytic hypertrophy and intercellular matrix in both groups.

• 한국임상약학회지
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• 제24권4호
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• pp.231-239
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• 2014

Background and objective: Pravastatin has been shown to have favorable risk-benefit profile when it is administered to hypercholesterolemic subjects to prevent cardiovascular events. However, subjects with impaired OATP1B1 activity may be more susceptible to pravastatin-induced muscle toxicity than subjects with normal OATP1B1 activity. A systematic review was conducted to evaluate the effect of SLCO1B1 genetic polymorphism on pharmacokinetics of pravastatin. Method: Medline$^{(R)}$ and Embase$^{(R)}$ were searched for relevant studies until July 2013. The search terms used were pravastatin AND (SLCO1B1 OR OATP1B1 OR LST1 OR SLC21A6) AND (gene OR $genetic^*$ OR $genomic^*$ OR $pharmacogenet^*$ OR $pharmacogenom^*$ OR $polymorph^*$). Results: A meta-analysis of the area under the concentration-time curve (AUC) of pravastatin in $SLCO1B1^*15$ and $SLCO1B1^*1a/^*1a$ was conducted. Five studies met all the inclusion criteria and methodological requirements. There was no statistically significant difference in the AUC value between $SLCO1B1^*15$ and $SLCO1B1^*1a/^*1a$ (p=0.728). However, $SLCO1B1^*15$ participants exhibited significantly higher AUC values than $SLCO1B1^*1b/^*1b$ carriers (p<0.001). In case of $SLCO1B1^*15^*15$ carriers, they had significantly higher AUC value than $SLCO1B1^*1a/^*1a$ subjects (p=0.002). Lastly, compared with to the subjects of $SLCO1B1^*1a/^*1a$, the carriers of heterozygous $SLCO1B1^*15$ increased the AUC value of pravastatin statistically significantly in Asian population (p=0.014). Conclusion: The present meta-analysis suggests that subjects with $SLCO1B1^*15$ are associated with increased AUC of pravastatin.