• Home
  • Search Results
  • Analysis of fast excitatory postsynaptic currents in bullfrog parasympathetic ganglion cells.

Analysis of fast excitatory postsynaptic currents in bullfrog parasympathetic ganglion cells.

The Journal of neuroscience : the official journal of the Society for Neuroscience (1983-11-01)
E A Connor, R L Parsons

Excitatory postsynaptic currents (EPSCs), miniature excitatory postsynaptic currents (MEPSCs), and acetylcholine-induced current fluctuations (noise) have been studied in voltage-clamped bullfrog parasympathetic ganglion cells of the atrial septum. EPSCs were also recorded from voltage-clamped sympathetic B cells and, in general, it was found that the basic properties of the EPSCs are similar in both parasympathetic and sympathetic B cells. For parasympathetic cells, the EPSC reached a peak amplitude of several nanoamperes within 3 msec and decayed exponentially. For 31 cells voltage-clamped to -50 mV (22 to 23 degrees C), peak amplitude was -4.3 +/- 1.4 nA (mean +/- SD) and the decay time constant, tau, was 5.6 +/- 1.0 msec. tau was independent of EPSC amplitude at a set voltage but increased with hyperpolarization, the coefficient of voltage dependence being -0.0070 +/- 0.0025 mV-1 in 13 cells (21 to 23 degrees C). The EPSC amplitude-voltage relationship was linear between -30 and -90 mV. The reversal potential, determined by interpolation, was -4.0 +/- 6.7 mV (n = 11). The EPSC tau had a Q10 equal to 2.9. Blocking the acetylcholinesterase with methane sulfonyl fluoride (MSF) pretreatment prolonged EPSC decay but decreased EPSC amplitude. In addition, EPSC decay after MSF treatment deviated from a single exponential function. MEPSCs exhibited decay characteristics very similar to those of EPSCs recorded at the same voltage and temperature. Acetylcholine-induced current fluctuations were well described by a single Lorentzian function with the estimated mean channel open time (tau noise) very similar to the EPSC decay time constant.(ABSTRACT TRUNCATED AT 250 WORDS)

Product Number
Product Description

Methanesulfonyl chloride, purum, ≥98.0% (AT)
Methanesulfonyl chloride, ≥99.7%