http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Bok-Hee Choi,Byung-Hyun Park,Yong-Geun Kwak 대한생리학회-대한약리학회 2004 The Korean Journal of Physiology & Pharmacology Vol.8 No.5
Cytolysin produced by <I>Vibrio vulnificus</I> has been incriminated as one of the important virulence determinants in <I>V. vulnificus</I> infection. Ion selectivity of cytolysin-induced pores was examined in a CPAE cell, a cell line of pulmonary endothelial cell, using inside-out patch clamp techniques. In symmetrical NaCl concentration (140 mM), intracellular or extracellular application of cytolysin formed ion-permeable pores with a single channel conductance of 37.5⁑4.0 pS. The pore currents were consistently maintained after washout of cytolysin. Replacement of Na<SUP></SUP> in bath solution with monovalent ions (K<SUP></SUP>, Cs<SUP></SUP> or TEA<SUP></SUP>) or with divalent ions (Mg<SUP>2</SUP>, Ca<SUP>2</SUP>) did not affect the pore currents.<FONT COLOR=BLUE><SPAN STYLE= font-size:11pt; > </SPAN>When the NaCl concentration in bath solution was lowered from 140 to 60 and 20 mM, the reversal potential shifted from 0 to 11.8 and 28.2 mV, respectively. The relative permeability of the cytolysin pores to anions measured at 40 mV was Cl<SUP></SUP> = NO<SUB>2</SUB><SUP></SUP> ≥ Br<SUP></SUP> = I<SUP></SUP> > SCN<SUP></SUP> > acetate<SUP></SUP> > isethionate<SUP></SUP> > ascorbic acid<SUP></SUP> > EDTA<SUP>2</SUP>, in descending order. The cytolysin-induced pore current was blocked by Cl<SUP></SUP> channel blockers or nucleotides. These results indicate that <I>V. vulnificus</I> cytolysin forms anion-selective pores in CPAE cells.
Effect of Genistein, a Tyrosine Kinase Inhibitor, on the Cloned Rat Brain Potassium Channel Kv1.5
Bok Hee Choi 대한생리학회-대한약리학회 2006 The Korean Journal of Physiology & Pharmacology Vol.10 No.5
The effect of genistein, widely used as a specific tyrosine kinase inhibitor, on rat brain Kv1.5 channels which were stably expressed in Chinese hamster ovary cells was investigated using the whole-cell patch-clamp technique. Genistein inhibited Kv1.5 currents at 50 mV in a concentration-dependent manner, with an IC<SUB>50</SUB> of 54.7⁑8.2μM and a Hill coefficient of 1.1⁑0.2. Pretreatment of Kv1.5 with protein tyrosine kinase inhibitors (10μM lavendustin A and 100μM AG1296) and a tyrosine phosphatase inhibitor (500μM sodium orthovanadate) did not block the inhibitory effect of genistein. The inhibition of Kv1.5 by genistein showed voltage-independence over the full activation voltage range positive to 0 mV. The activation (at 50 mV) kinetics was significantly delayed by genistein: time constant for an activation of 1.4⁑0.2 msec under control conditions and 10.0⁑1.5 msec in the presence of 60μM genistein. Genistein also slowed the deactivation of the tail currents, resulting in a crossover phenomenon: a time constant of 11.4⁑1.3 msec and 40.0⁑4.2 msec under control conditions and in the presence of 60μM genistein, respectively. Inhibition was reversed by the application of repetitive depolarizing pulses, especially during the early part of the activating pulse. These results suggest that genistein directly inhibits Kv1.5 channels, independent of phosphotyrosine-signaling pathway.