• Archives of Pharmacal Research
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• 제17권6호
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• pp.405-410
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• 1994

The present study was undetertaken to demonstrate whether or not angiotensin II activates a phopholipase D in rabbit kidney proximal tubule cells. By measuring the formation of [$^3H$] phosphatidic acid and [$^3H$]diacylglycerol. This result suggests that some phosphatidic acid seems to be formed directly from phosphatidylcholin by the action of phopholipase D, not from the action of diacylglycerol kinase on the diacylglycerol. In addition the other mechanisms by which phospholipase D is activated was examined. We have found that phospholipase D was activited by extracellular calium ion. It has also been shown that angiotensin II may activate phosphoilpase D through protein kinase C-independent pathway.

• Tuberculosis and Respiratory Diseases
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• 제43권2호
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• pp.123-127
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• 1996

Secretion of surfactant phospholipid can be stimulated by a variety of agonists acting via at least three different signal transduction mechanisms. These include the adenylate cyclase system with activation of cAMP-dependent protein kinase; activation of protein kinase C either directly or subsequent to activation of phosphoinositide-specific phospholipase C and generation of diacylglycerols and inositol trisphosphate; and a third mechanism that involves incresed $Ca^{2+}$ levels and a calmodulin-dependent step. ATP stimulates secretion via all three mechanisms. The protein kinase C pathway is also coupled to phopholipase D which, acting on relatively abundant cellular phospholipids, generates diacylglycerols that further activate protein kinase C. Sustained protein kinase C activation can maintain phosphatidylcholine secretion for a prolonged period of time. It is likely that interactions between the different signaling pathways have an important role in the overall physiological regulation of surfactant secretion.

• 대한화학회지
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• 제41권12호
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• pp.672-676
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• 1997

쥐의 미크로좀 포스포리파제 D(PLD)를 센 이온세기 상태에서 0.2% taurodeoxycholate를 사용하여 용해시켰다. 포스포리파제 D의 활성은 기질로 방사성 동위원소로 표지 된 dipalmitoylphophatidylcholine을 사용하여 생성된 phosphatidic acid(PA)를 측정하여 결정하였다. 용해된 PLD의 초적 pH와 온도는 각각 6.5와 30$^{\circ}C$로서 용해되기 전 미크로좀 상태의 PLD와 비슷하였다. 올레산의 활성화 효과는 4 mM 농도에서 관찰되었다. PLD 활성도에 미치는 금속이온 영향을 조사한 결과 $Mg^{2+},\; Ca^{2+},\; Sr^{2+}, \;Ba^{2+}$와 같은 알칼리 토금속은 모두 PA 생성을 촉진시킨 반면, $Cu^{2+},\; Cd^{2+},\; Al^{3+},\; Ni^{2+},\; V^{5+}$는 억제하였다.

• Molecules and Cells
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• 제27권3호
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• pp.383-390
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• 2009

To investigate the regulatory mechanism underlying the contractile response in the intestinal smooth muscle of the nile tilapia (Orechromis niloticus), we used pharmacologic and molecular approaches to identify the muscarinic subreceptors and the intracellular signaling pathways involved in this motility. Myography assays revealed that an M1- and M3-subtype selective antagonist, but not a M2-subtype selective antagonist, inhibited carbachol HCl (CCH)-induced intestinal smooth muscle contraction. In addition, a phospholipase C inhibitor, but not an adenylate cyclase inhibitor, blocked the contractile response to CCH. We also cloned five muscarinic genes (OnM2A, OnM2B, OnM3, OnM5A, and OnM5B) from the nile tilapia. In the phylogenetic analysis and sequence comparison to compare our putative gene products (OnMs) with the sequences obtained from the near complete teleost genomes, we unexpectedly found that the teleost fish have respectively two paralogous genes corresponding to each muscarinic subreceptor, and other teleost fish, except zebrafish, do not possess muscarinic subreceptor M1. In addition, the expression pattern of the nile tilapia muscarinic subreceptor transcripts during CCH-induced intestinal smooth muscle contraction in the proximal intestinal tissue was analyzed by real-time PCR surveys and it was demonstrated that CCH increased the OnMs mRNA expression rapidly and transiently.

• 대한후두음성언어의학회지
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• 제12권2호
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• pp.126-132
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• 2001

Background and Objectives : Signal traduction through phospholipase C(PLC) participate in the regulation of cell growth and differentiation. Growth factors bind to their receptors and thereby induce tyrosine phophorylation of the phospholipase C-${\gamma}$1(PLC-${\gamma}$1). PLC-${\gamma}$1 is a substrate for several receptor tyrosine kinases and its catalytic activity is increased by tyrosine phosphorylation. Tyrosine kinase phosphorylation of PLC-${\gamma}$1 stimulates PLC activation and cell proliferation. However the signal transduction pathway and the significance of PLC in injured recurrent laryngeal nerve regeneration is unknown. Therefore after we obtained fuctionally recovered rats using PEMF in this study, we attempt to provide some evidence that PLC plays a role in nerve regeneration itself and regeneration related to PEMF through the analysis of the difference between fucntional recovery group and non-recovery group in the recurrent laryngeal nerve. Materials and Method : Using 32 healthy male Sprague-Dawley rats, transections and primary anastomosis were performed on their left recurrent laryngeal nerves. Rats were then randomly assigned to 2 groups. The experimental group(n=16) received PEMS by placing them in custom cages equipped with Helm-holz coils(3hr/day, 5days/wk, for 12wk). The control group(n=16) were handled the same way as the experimental group, except that they did not receive PEMS. Laryngo-videoendoscopy was performed before and after surgery and followed up weekly. Laryngeal EMG was obtained in both PCA and TA muscles. Immunohistochemisty staining and Western blotting analysis using monoclonal antibody was performed to detect PLC-${\gamma}$1 in recurrent laryngeal nerve and nodose ganglion. Results : 10 rats(71%) in experimental group and 4 rats(38%) in the control group showed recovery of vocal fold motion. Functionally-recoverd rats show PLC-${\gamma}$1 positive cells in neuron and ganglion cells after 12 weeks from nerve injury. Conclusion : This study shows that PLC1-${\gamma}$ involved in singnal trasduction pathway in functinal recovery of injured recurrent laryngeal nerve and PEMF enhance the functional recovery by effect on this molecule.

• 한국미생물·생명공학회지
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• 제32권1호
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• pp.78-83
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• 2004

국내 6개 지역에 걸쳐 채취한 토양 63점으로부터 1,000여 종의 방선균주를 분리하였다. 이들 균주의 배양 상징액 중 PLD의 생산이 양호한 균주를 탐색한 결과, 분해활성이 0.3U/$m\ell$이상인 131 균주를 일차로 선발하였다. 이중 전이 활성이 20% 이상인 균주는 23개였으며, 최종적으로 분해 및 전이활성이 가장 우수한 균주(방선균 KF923)를 선발하였다. 방선균 KF923 균주는 P 배지하에서 발효조 배양시 배양 48시간 후에 최고의 분해활성을 나타내었고(13U/$m\ell$) 전이활성은 95%로 나타났다. 방선균 KF923 균주가 생산한 PLD를 정제하여 비활성이 567U/mg의 PLD를 얻었다. 정제된 PLD는 분자량이 약 55kD으로 나타났고, 효소반응의 최적 pH는 6.0, 최적온도는 $60^{\circ}C$였으며, 효소의 안정성에 미지는 pH 및 온도의 영향은 pH 8.0부근 및 $40^{\circ}C$ 이하에서 가장 안정하였다. 또한, 특별한 금속이온의 요구성은 없는 것으로 나타났다. 방선균 KF923 균주가 생산한 PLD는 산업화에 충분히 활용 가능하며, 이를 위하여 효소의 대량생산 및 효소반응을 위한 공정개발 등의 연구가 필요하다고 생각한다.

• 한국미생물·생명공학회지
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• 제31권4호
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• pp.389-394
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• 2003

국내 6개 지역에 걸쳐 채취한 토양 63점으로부터 1,000여 종의 방선균주를 분리하였다. 이들 균주의 배양 상징액중 PLD의 생산이 양호한 균주를 탐색한 결과, 분해활성이 0.3 U/ml 이상인 131 균주를 일차로 선발하였다. 이중 전이활성이 20% 이상인 균주는 23 개였으며, 최종적으로 분해 및 전이활성이 가장 우수한 균주(방선균 KF923)를 선발하였다. 방선균 KF923 균주는 P배지하에서 발효조 배양시 배양 48시간후에 최고의 분해활성을 나타내었고(13 U/ml) 전이활성은 95%로 나타났다. 방선균 KF923 균주가 생산한 PLD를 정제하여 비활성이 567 U/mg의 PLD를 얻었다. 정제된 PLD는 분자량이 약 55 kD으로 나타났고, 효소반응의 최적 pH는 6.0, 최적온도는 $60^{\circ}C$였으며, 효소의 안정성에 미치는 pH 및 온도의 영향은 pH 8.0부근 및 $40^{\circ}C$ 이하에서 가장 안정하였다. 또한. 특별한 금속이온의 요구성은 없는 것으로 나타났다. 방선균 KF923 균주가 생산한 PLD는 산업화에 충분히 활용 가능하며, 이를 위하여 효소의 대량생산 및 효소반응을 위한 공정개발 등의 연구가 필요하다고 생각한다.