Myoung Kyu PARK, M.D.Ph.D.Associate Professor Contact    Tel: +82-31-299-6101    Fax: +82-31-299-6129    e-mail: mkpark@med.skku.ac.kr

Background:

Research:

- Calcium Signaling and Ion Channels
- Neuronal Excitability and Dopamine Neuron Physiology
- Live Cell Imaging / Fluorescence Imaging / Molecular Imaging

Ca signalling has been received a particular attention because of its wide engagement and ubiquity in all kinds of cells. The variety of functions of Ca ion involved in contraction, secretion, neurotransmitter release, gene expression, proliferation/differentiation, and apoptosis now appear to be understood in the view of complex spatiotemporal Ca changes. To understand the exact mechanisms in which the basic function of each cell involved, we need specific information about the Ca dynamics of spatiotemporal patterns of Ca changes in the cytosol as well as in the suborganelles. The main intracellular Ca store is ER and other participants are such as Golgi apparatus, nucleus envelope, secretory granules and mitochondria. We have showed that the whole ER is functionally connected and small molecules including Ca are quickly equilibrated. This is the first direct demonstration of Ca2+ movement in the lumen of ER. We also firstly showed the presence of functionally distinct mitochondria within a single cell. It explains how the mitochondria located in the specific position in the cell give a specific role. All these experiments have been done in the isolated pancreatic acinar cells. Now we are expanding our knowledge of Ca signaling into neuronal cells. The final objective is to understand how the complex spatiotemporal Ca events work and the physiological roles in these normal cells. In addition, we are expanding our research interests into the functional organization of intracellular signals and organelles at the single cell level in neuronal cells. Thus we now are actively investigating the neuronal excitability and signal transduction mechanisms in dopamine neurons. To do this, we have established real time imaging techniques with patch clamp systems. The powerful combined techniques between molecular techniques, high resolution fluorescence imaging, laser scanning confocal microscopy, and patch clamp techniques will lead us to the deep sites of intracellular signaling.

Publications:

1. Choi YM, Jang JY, Jang M, Kim SH, Kang YK, Cho H, Chung S, Park MK. Modulation of firing activity by ATP in dopamine neurons of the rat substantia nigra pars compacta. Neuroscience 2009 (in press)
2. Kim YJ, Park MK Chung S. Voltage-operated Ca2+ channels regulate dopamine release from somata of dopamine neurons in the substantia nigra pars compacta. Biochem Biophys Res Commun373(4):665-9. 2008.9
3. Jin TE, Jang MA, Kim HJ, Choi YM, Cho H, Chung S,Park MK. Involvement of corticotropin-releasing factor receptor in differentiation of dopaminergic MN9D cells. Molecules and Cells 26: 243-249 2008.9
4. Park MK, Choi YM, Kang YK, Petersen OH. The Endoplasmic Reticulum as an Integrator of Multiple Dendritic Events. Neuroscientist 14(1): 68-77. 2008.02
5. Kim YJ, Park MK, Uhm DY, Chung S. Modulation of T-type Ca2+ Channels by Corticotropin-Releasing Factor through protein kinase C pathway in MN9D dopaminergic cells. Biochemical and Biophysical Research Communications 358:796-801, 2007.07.
6. Kim SH, Choi YM, Jang JY, Chung S, Kang YK, Park MK. Non-selective cation channels are essential for maintaining intracellular Ca2+ levels and spontaneous firing activity in the midbrain dopamine neurons Pflugers Archiv-European Journal of Physiology 455(2):309-321, 2007.11
7. Landman N, Jeong SY, Shin SY, Voronov SV, Serban G, Kang MS, Park MK, Di Paolo G, Chung S, Kim TW. Presenilin mutations linked to familial Alzheimer's disease cause an imbalance in phosphatidylinositol-4,5-bisphosphate metabolism Proceedings of the National Academy of Sciences of the USA (PNAS) 103:19524-19529. 2006.12
8. Choi YM, Kim SH, Chung S, Uhm DY,Park MK. Regional interaction of endoplasmic reticulum Ca2+ signals between soma and dendrites through rapid luminal Ca2+ diffusion. Journal of Neuroscience 26(47):12127-12136. 2006.11 (selected as "The week of The Journal")
9. Jeong SY, Shin SY, Kim HS, Bae CD, Uhm DY, Park MK, Chung S. Regulation of magnesium-inhibited cation current by actin cytoskeleton rearrangement. Biochemical and Biophysical Research Communications 339:810-815. 2006.01
10. Kim YJ, Park MK, Uhm DY, Chung S. Chung S. Modulation of delayed rectifier potassium channels by ? alpha1-adrenergic activation via protein kinase Czeta and p62 in PC12 cells Neuroscience Letters 387, 43-48. 2005.09
11. Lee M, Chung S, Uhm DY, Park MK. Regulation of zymogen granule exocytosis by Ca2+, cAMP, and PKC in pancreatic acinar cells Biochemical and Biophysical Research Communications 334: 1241-1246. 2005.08
12. Kang YK, Park MK. Endoplasmic reticulum Ca2+ store: regulation of Ca2+ release and reuptake by intracellular and extracellular Ca2+ in pancreatic acinar cells Molecules and Cells 19(2): 268-278. 2005
13. Kim SH, Choi YM, Chung S, Uhm DY, Park MK. Two different Ca2+-dependent inhibitory mechanisms of spontaneous firing by glutamate in dopamine neurons. Journal of Neurochemistry 91(4):983-995. 2004
14. Park MK, Lee MS, Petersen OH. Morphological and functional changes of dissociated single pancreatic acinar cells: testing the suitability of the single cell as a model for exocytosis and calcium signaling.Cell Calcium. 35(4):367-379. 2004
15. Choi YM, Kim SH, Uhm DY, Park MK. Glutamate-mediated [Ca2+]c dynamics in spontaneously firing dopamine neurons of the rat substantia nigra pars compacta. Journal of Cell Science 116(13):2665-2675. 2003
    
16. Lee KK, Uhm DY, Park MK. Low affinity cholecystokinin receptor inhibits cholecystokinin- and bombesin-induced oscillations of cytosolic Ca2+ concentration. FEBS Letters.538:134-138. 2003
    
17. Kang TM, Park MK, Uhm DY. Effects of hypoxia and mitochondrial inhibition on the capacitative calcium entry in rabbit pulmonary arterial smooth muscle cell. Life Sciences. 72(13):1467-1479. 2003.
    
18. Ashby MC, Craske M, Park MK, Gerasimenko OV, Burgoyne RD, Petersen OH, Tepikin AV. Localized Ca2+ uncaging reveals polarized distribution of Ca2+-sensitive Ca2+ release sites: mechanism of unidirectional Ca2+ waves. Journal of Cell Biology. 158(2):283-292. 2002
    
19. Park MK, Tepikin AV, Petersen OH. What can we learn about cell signalling by combining optical imaging and patch clamp techniques? Pflugers Archiv-European Journal of Physiology. 444(3):305-316, 2002.
    
20. Park MK, Lee KK, Uhm DY. Slow depletion of endoplasmic reticulum Ca2+ stores and block of store-operated Ca2+ channels by 2-aminoethoxydiphenyl borate in mouse pancreatic acinar cells. Naunyn Schmiedeberg’s Archives of Pharmacology. 365(5) 113-119. 2002
    
21. Kang TM, Park MK, Uhm DY. Characterization of hypoxia-induced [Ca2+]i rise in rabbit pulmonary arterial smooth muscle cells. Life Sciences. 70(19):2321-2333. 2002
    
22. Park MK, Lomax RB, Tepikin AV, Petersen. OH. Local uncaging of caged Ca2+ reveals distribution of Ca2+-activated Cl- channels in pancreatic acinar cells. Proceedings of the National Academy of Sciences of the USA (PNAS). 98(19):10948-10953, 2001
    
23. Petersen OH, Tepikin AV, Park MK. The endoplasmic reticulum: one continuous or several separate Ca2+ stores? Trends in Neuroscience 24(5):271-276, 2001
    
24. Park MK, Ashby MC, Erdemli G, Petersen OH, Tepikin AV. Perinuclear, perigranular and sub-plasmalemmal mitochondria have distinct functions in the regulation of cellular calcium transport. EMBO Journal, 20(8): 1863-1874, 2001
    
25. Park MK, Petersen OH, Tepikin AV. The endoplasmic reticulum as one continuous Ca2+ pool: visualization of rapid Ca2+ movements and equilibration. EMBO Journal, 19(21):5729-5739, 2000
    
26. Rhee PL, Kim CH, Park MK, Kim YI, Rhee JC, Kim KW, Uhm DY, Kang TM. Hypotonic stretch increases L-type calcium current in smooth muscle cells of the human stomach. Experimental Physiology 85(5):497-504, 2000
    
27. Rhee JC, Rhee PL, Park MK, So I, Uhm DY, Kim KW, Kang TM. Muscarinic receptors controlling the carbachol-activated nonselective catioic current in guinea-pig gastric smooth muscle cells. Japanese Journal of Pharmacology 82(4):331-337, 2000
    
28. Park MK, Tepikin AV, Petersen OH. The relationship between acetylcholine-evoked Ca2+-dependent current and the Ca2+ concentrations in the cytosol and the lumen of the endoplasmic reticulum in pancreatic acinar cells. Pflugers Archiv-European Journal of Physiology, 438: 760-765, 1999.
    
29. Park MK, Kang TM, Uhm DY, Lee SJ, Lee SH, Ho WK, Earm YE. Different contractile properties between intralobar and extralobar pulmonary arteries of the rabbit. Journal of Smooth Muscle Research, 35(1):1-10, 1999.
    
30. Kang TM, Xu W, Kim SJ, Ahn SC, Kim YC, So I, Park MK, Uhm D-Y, Kim KW. Evidence for adenosine triphosphate (ATP) as an excitatory neurotransmitter in guinea-pig gastric antrum. Korean Journal of Physiology and Pharmacology, 3:165-174, 1999
    
31. Bae YM, Park MK, Lee SH, Ho WK, Earm YE. Contribution of Ca2+-activated K+ channel and non-selective cation channel to membrane potential of pulmonary arterial smooth muscle cells of the rabbit, Journal of Physiology-London, 514(3):747-758, 1999
    
32. Song DK, Park MK. Hypoxic pulmonary vasoconstriction and change in outward K current in pulmonary arterial smooth muscle cell of the rabbit. The Korean Journal of Aerospace and Environmental Medicine, 9(2):171-175, 1999
    
33. Lee SH, Park MK. The role of intracellular Mg2+ in regulation of Ca2+-activated K+ channel in pulmonary arterial smooth muscle cells of the rabbit. Korean Journal of Physiology and Pharmacology, 2:611-616, 1998
    
34. Song DK, Park WK, Bae JH, Park MK, Kim SJ, Ho WK, Earm YE. Reduced dihydroxyacetone sensitivity and normal sensitivity to glyceraldehyde and oxidizing agent of ATP-sensitive K channels of pancreatic beta cells in NIDDM rats. Journal of Korean Medical Science, 12(4), pp286-292, 1997
    
35. Park MK, Bae YM, Lee SH, Ho WK, Earm YE. Modulation of voltage-dependent K channels by redox potential in pulmonary and ear arterial smooth muscle cells of the rabbit. Pflugers Archiv-European Journal of Physiology 434:764-771, 1997
    
36. Park MK, Lee SH, Ho WK, Earm YE. Redox agents as a link between hypoxia and the responses of ionic channels in pulmonary vascular smooth muscle, Experimental Physiology. 80:835-842, 1995
    
37. Park MK, Lee SH, Lee SJ, Ho WK, Earm YE. Different modulation of Ca-activated K channels by the intracellular redox potential in pulmonary and ear arterial smooth muscle cells of the rabbit. Pflugers Archiv-European Journal of Physiology 430:308-314, 1995
    
38. Lee SH, Park MK, So IS, Earm YE. NADH and NAD modulate Ca-activated K channels in small pulmonary arterial smooth muscle cell of the rabbit. Pflugers Archiv-European Journal of Physiology 427: 378-380, 1994
    
39. Kim SJ, Lim W, Park MK, Lee J, Kim J. Discharge patterns and peripheral nerve inputs to cardiovascular neurons in the medulla of cats: comparison between the lateral and medial medulla. Korean Journal of Physiology, 28 (2):133-141, 1994
    
40. Park MK, Earm YE. Effects of metabolic inhibition and acidosis on the contractility of the pulmonary and ear artery. Seoul Journal of Medicine 35, N0.4:231-237, 1994

Chapters in Books:

1. Kim SH & Park MK. "Ch 7. Ca2+ caging and uncaging." in Introduction: Principles of Ca2+ homeostasis and Ca2+ signalling and Ca2+ measurements." O.H. Petersen & A. Verkhratsky, Elservier, 2009 (in press)