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The purpose of this paper, the use of the patch-clamp technique, using the inside-outside-recording method, research procaine concentration on the delayed rectifier K ~ channels in cortical pyramidal neurons, and then explore procaine on the central role of molecular mechanism. Neurons acutely isolated 2 to 5-day-old SD rats, male or female, decapitated, the brain lift take-cortex and cut into thin brain slices, placed to the calcium, magnesium artificial cerebrospinal fluid (ACSF wind and percussion), placed in artificial cerebrospinal fluid containing 2.5% trypsin digestion. Draw 3-5 drops of the cell suspension after digestion, applied to be handled by poly-L-lysine coverslips, adherent cells into the high potassium bathing solution. 2 experimental groups procaine joined by the micro pipette divided into eight groups: 0 (control group), 0.2,0.4,0.8,1.6,2.4,3.2,4.0 mmol / L, according to their concentration. Each group of seven different clamping voltage, observe the 11 samples. 3 single-channel recording using the patch-clamp technique-oriented outside the single-channel current, drawn two-step electrode puller electrode resistance of 10 to 12MΩ heating levels were 65,57, tip-off diameter of about 0.5 to 1μm , filling high potassium electrode solution. Current is amplified by the patch-clamp amplifier the probe feedback resistor 10GΩ, low-frequency filter frequency of 1 kHz (3 dB, 4-Bessel), with the PCM recorder records. 4 data analysis signal by the Digidata 1200 interface data acquisition system, and 6.04 Pclamp collection procedures, sampling frequency, 5kHz, switching time ignore the level of 200 s. The original data entry p III -300 computer, automatic measurement of the current amplitude of the channel, the channel opening and closing time, and then enter the pstat for preliminary statistical processing with FETCHAN analysis program. Using SPSS 8.0 statistical software with various concentrations of linear Sino-Japanese People's Liberation Army, First Military Medical University, a master's degree thesis regression analysis, conductivity, respectively, in different cells, the clamp voltage or l and drug concentration as grouping variables, analysis of quantitative variables, including current amplitude, conductance, and channel switching dynamics change; various procaine concentrations between current amplitude, conductance, and channel switching kinetic parameters of the difference of variance analysis. Delay confirmation and characteristics of the the turtle stream justice ret ju within a certain range, the channel current amplitude with depolarization level increases with the clamping voltage changes, the current amplitude obtained - membrane potential vs. O-V curve) linearly. Each of the clamp voltage and the average current amplitude relationships reflect the current amplitude of the voltage dependence. A clamping voltage, current amplitude. The scatter plot of the opening hours of open events are concentrated in a certain level of current amplitude, can be drawn by calculating the advantage conductance of 52 ± 2.4ps, also showed significant voltage-dependent. Using inside out or set of experiments in the liquid, the reversal potential of the channel (Rerersa Potential EJ close to OMV; 140mmol of CsCl instead of KCI in the bathing solution, the channel current disappeared; but with 20 mm l the adjoin instigate amino (-AP) to replace the original bath, the channel current activity did not change. the TTX and the low calcium entire solution EGTA glycol double-amino ethyl acetate) block sodium, calcium through t chloride channel is difficult to record, and thus confirmed the delay flow K +1 Road. Two procaine impact on the soup flow K31jt extended chase zl late invited the current amplitude cartridge conductance control group and 7 procaine respective I-V curve of the concentration group substantially straight line, namely for the experimental record single late Road; 0.4mml Bu-V relations helical string minimum channel conductance of the lowest o6 ± 1.4 ps Bu then increased gradually with the increase of the concentration conductance ~ 4 ~ First Military Medical University Master soil dissertation and Z4mmol, the highest conductance value of O0 ± 2 knife into yesterday. Open probability of adverse effects on the control group dynamics of ZRtrjljN open for the lead. 6% ± 3.9%, when the concentration increased to 0.4mmol open probability dropped to 26.2% ± 2.0%; Later, with the increase of drug concentration open probability gradually increased up to 78% ± 5 .9%. In terms of the relationship between voltage and open probability increased clamping voltage O towel, open probability gradually decreases, the diaphragm electrode transmembrane potential Vin =-Vp, Vp both the more close to VRE, VIN is the more close to the resting membrane potential, and thus the probability of its open gradually approaches zero. 2.3 of open time constant of the adverse effects on short-term control group channel open time constant. ;) 0 to 75 ± 6.329ms when the bathing solution. Zmmol procaine, or even lower concentration, \\; immediately reduced to 5 soil 2.402ms, and thereafter \\; no significant changes in long the process opening hours constant h with the drug concentration. . Slightly lower) after joining the drug, when the drug concentration is increased to 0.4mmol. * Reduced to 24 ± 3.202ms, a decrease of approximately 15 ± 1.4325, the drug concentration of 0. smmol \\. And the level of dosing; in turn in 1.6 nunol T. Up to the highest point, ie 73 ± 5.307ths; later with the increase of drug concentration \\ 2-way downward trend; opening hours basic and long-range opening hours constant T. . Corresponding to. And 4 off time and off time constant of channel closing time constant h. ) Control group was 78.566 ± 16.9761: IFS extend the closing time, after joining the drug procaine concentration of 0.4mmol off time of 303.727 ± 78.3465, after closing time with increasing concentration gradually becomes short, a concentration of 1.6
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